Finding the second highest number in array

Question

I m having difficulty to understand the logic behind the method to find the second highest number in array  The method used is to find the highest in the array but less than the previous highest  which has already been found   The thing that I still can t figure it out is why    highest score    second highest is necessary  For example I input three numbers  98  56  3  Without it  both highest and second highest would be 98  Please explain   int second highest   score 0     if  score i   gt  second highest  amp  amp  score i   lt  highest score    highest score    second highest         second highest   score i

User · Answer

public void findMax int a          int large   Integer MIN VALUE      int secondLarge   Integer MIN VALUE      for  int i   0  i  lt  a length  i              if  large  lt  a i                 secondLarge   large              large   a i             else if  a i   gt  secondLarge                if  a i     large                    secondLarge   a i                                     System out println  Large number     large     Second Large  number     secondLarge       The above code has been tested with integer arrays having duplicate entries  negative values  Largest number and second largest number are retrived in one pass  This code only fails if array only contains multiple copy of same number like  8 8 8 8  or having only one number

User · Answer

The second largest element in the array   IN Java   class test2      public static void main String   args     int a      1 2 3 9 5 7 6 4 8   Arrays sort a   int aa   a a length -2    System out println aa            main     end   In Python    a    1  2  3  9  5  7  6  4  8   aa   sorted list a   print aa  aaa   aa -2  print aaa

User · Answer

I think for finding the second Highest no we require these lines if we can use inbuilt function  int   randomIntegers    1  5  4  2  8  1  1  6  7  8  9       Arrays sort randomIntegers       System out println randomIntegers randomIntegers length-2

User · Answer

Please try this one  Using this method  You can fined second largest number in array even array contain random number  The first loop is used to solve the problem if largest number come first index of array   public class secondLargestnum        public static void main String   args               TODO Auto-generated method stub         int   array   new int 6           array 0    10          array 1    80          array 2    5          array 3    6          array 4    50          array 5    60          int tem   0          for  int i   0  i  lt  array length  i                  if  array 0  gt array i                     tem   array 0               array 0    array array length-1               array array length-1    tem                                  Integer largest   array 0           Integer second largest   array 0            for  int i   0  i  lt  array length  i                   if  largest lt array i                     second large   largest                  largest   array i                             else if  second large lt array i                     second large   array i                             System out println  largest number   largest   and second largest number   second largest

User · Answer

My idea is that you assume that first and second members of the array are your first max and second max  Then you take each new member of an array and compare it with the 2nd max  Don t forget to compare 2nd max with the 1st one  If it s bigger  just swap them      public static int getMax22 int   arr       int max1   arr 0       int max2   arr 1       for  int i   2  i  lt  arr length  i             if  arr i   gt  max2                        max2   arr i                      if  max2  gt  max1                        int temp   max1              max1   max2              max2   temp                       return max2

User · Answer

import java util Scanner   public class SecondLargest        public static void main String   args            Scanner sc   new Scanner System in           System out print  Enter size of array               int n   sc nextInt            int ar     new int n           for int i 0 i lt n i                          System out print  Enter value for array                   ar i    sc nextInt                      int m ar 0  m2 ar 0           for int i 0 i lt n i                          if ar i  gt m                  m ar i                     for int i 0 i lt n i                          if ar i  gt m2  amp  amp  ar i  lt m                  m2 ar i                     System out println  Second largest     m2           sc close

User · Answer

public static void main String   args         int   arr    0 12 74 56 2 63 45       int f1   1  f2   0  temp   0      int num   0       for  int i   0  i  lt  arr length  i             num   arr i           if  f1  lt  num                temp   f1              f1   num              num   temp                    if  f2  lt  num                temp   f2              f2   num              num   temp                      System out println  First Highest     f1     Second Highest     f2     Third     num

User · Answer

If time complexity is not an issue  then You can run bubble sort and within two iterations  you will get your second highest number because in the first iteration of the loop  the largest number will be moved to the last  In the second iteration  the second largest number will be moved next to last

User · Answer

Use following function    public static int secHigh int arr                 int firstHigh   0 secHigh   0              for int x  arr                   if x  gt  firstHigh                       secHigh   firstHigh                      firstHigh   x                   else if x  gt  secHigh                       secHigh   x                                              return secHigh              Function Call  int secondHigh   secHigh arr

User · Answer

This is my answer in C   O N  complexity time  Pass the array only once  only three variables  The solution is very intuitive and easy to understand        include  lt stdio h gt       int second int arr   int size                int i  max   secondmax           if  arr 0   gt  arr 1                max   arr 0               secondmax   arr 1             else               max   arr 1               secondmax   arr 0                     for  i   2  i  lt  size  i                          if   arr i   lt  max   amp  amp   arr i   lt  secondmax                     continue                            if   arr i   lt  max   amp  amp   arr i   gt  secondmax                     secondmax   arr i                   continue                            if   arr i   gt  max                     secondmax   max                  max   arr i                   continue                                  return secondmax            void main                 int arr       1 10 5 7           int size   sizeof arr    sizeof arr 0            int secondmax   second arr size           printf   d  n n   secondmax

User · Answer

Find the second largest number   public class SecondMaxNumbers        public void printTwoMaxNumbers int   nums           int maxOne   0          int maxTwo   0          for int n nums               if maxOne  lt  n                   maxTwo   maxOne                  maxOne  n                else if maxTwo  lt  n                   maxTwo   n                                  System out println  Second Max Number    maxTwo              public static void main String a             int num      10 20 30 40 50 60 70           SecondMaxNumbers sec   new SecondMaxNumbers            tmn printTwoMaxNumbers num

User · Answer

This java program help to find second highest number in any given array  First we have to get highest value and then we have to go second one   class Demo      public static void main String args             int arr    321 321 321 43 65 234 56 -1 4 45 -67           int max arr 0           int len arr length          for int i 0 i lt len i                 if max lt arr i                    max arr i                                    System out println  Max value is   max            int secMax arr 0           for int j 0 j lt len j                 if max gt arr j                    if secMax lt arr j                        secMax arr j                                     else if secMax gt arr j                        secMax arr j                                                else if max  arr j                                                                System out println  Sec Max value is   secMax

User · Answer

If this question is from the interviewer then please DONT USE SORTING Technique or Don t use any built in methods like Arrays sort or Collection sort  The purpose of this questions is how optimal your solution is in terms of performance so the best option would be just implement with your own logic with O n-1  implementation  The below code is strictly for beginners and not for experienced guys      public void printLargest          int num      900 90 6 7 5000 4 60000 20 3        int largest   num 0        int secondLargest   num 1        for  int i 1  i lt num length  i                  if largest  lt  num i                         secondLargest   largest              largest   num i                       else if secondLargest  lt  num i                secondLargest   num i                       System out println  Largest      largest       System out println  Second Largest     secondLargest

User · Answer

public class SecondHighest        public static void main String   args               TODO Auto-generated method stub                        Find the second largest int item in an unsorted array             This solution assumes we have atleast two elements in the array            SOLVED  - Order N              Other possible solution is to solve with Array sort and get n-2 element             However  Big O  time NlgN                       int   nums   new int   1 2 4 3 5 8 55 76 90 34 91           int highest cur  secondHighest   -1           int arrayLength   nums length          highest   nums 1   gt  nums 0    nums 1    nums 0           secondHighest   nums 1   lt  nums 0    nums 1    nums 0            if  arrayLength    2                System out println secondHighest              else                for  int x   0  x  lt  nums length  x                       cur   nums x                   int tmp                   if  cur  lt  highest  amp  amp  cur  gt  secondHighest                      secondHighest   cur                   else if  cur  gt  secondHighest  amp  amp  cur  gt  highest                        tmp   highest                      highest   cur                      secondHighest   tmp                                                   System out println secondHighest

User · Answer

int arr      25  5  35  26  6  270  0    int large1   arr 0   int large2   arr 1    for  int i   2  i  lt  arr length  i           if  arr i   gt  large1             if  large1  gt  large2              large2   large1          large1   arr i          else if  arr i   gt  large2          large2   arr i                          System out println  Large1     large1   System out println  Large2     large2

User · Answer

If the first element which second highest is set to initially is already the highest element  then it should be reassigned to a new element when the next element is found  That is  it s being initialized to 98  and should be set to 56  But  56 isn t higher than 98  so it won t be set unless you do the check   If the highest number appears twice  this will result in the second highest value as opposed to the second element that you would find if you sorted the array

User · Answer

public class SecondandThirdHighestElement       public static void main String   args            int   arr    1 1 2 3 8 1 2 3 3 3 2 3 101 6 6 7 8 8 1001 99 1 0              create three temp variable and store arr of first element in that temp variable so that it will compare with other element         int firsttemp   arr 0           int secondtemp   arr 0           int thirdtemp   arr 0             check and find first highest value from array by comparing with other elements if found than save in the first temp variable          for  int i   0  i  lt  arr length  i                  if firsttemp  lt arr i                    firsttemp    arr i                  if             for           check and find the second highest variable by comparing with other elements in an array and find the element and that element should be smaller than first element array         for  int i   0  i  lt  arr length  i                  if secondtemp  lt  arr i   amp  amp  firsttemp gt arr i                    secondtemp   arr i                  if            for           check and find the third highest variable by comparing with other elements in an array and find the element and that element should be smaller than second element array          for  int i   0  i  lt  arr length  i                  if thirdtemp  lt  arr i   amp  amp  secondtemp gt arr i                    thirdtemp   arr i                  if            for          System out println  First Highest Value   firsttemp           System out println  Second Highest Value   secondtemp           System out println  Third Highest  Value   thirdtemp           main    class

User · Answer

I have got the simplest logic to find the second largest number may be  it s not  The logic find sum of two number in the array which has the highest value and then check which is greater among two simple              int ar    611 4 556 107 5 55 811   int sum ar 0  ar 1   int temp 0  int m ar 0   int n ar 1   for int i 0 i lt ar length i         for int j i j lt ar length j             if i  j           temp ar i  ar j           if temp gt sum               sum temp              m ar i               n ar j                     temp 0                 if m gt n       System out println n      else      System out println m

User · Answer

import java util    public class SecondLargestNew       public static void main String args                  int   array    0 12 74 26 82 3 89 8 94 3          int highest   Integer MIN VALUE      int secondHighest   Integer MIN VALUE        for  int i   0  i  lt  array length  i                   if  array i   gt  highest                               shift the current highest number to second highest             secondHighest   highest                    and set the new highest              highest   array i             else if  array i   gt  secondHighest                               Just replace the second highest             secondHighest   array i                           System out println  second largest is   secondHighest        System out println  largest is    highest

User · Answer

import java util Scanner   public class SecondHighestFromArrayTest    public static void main String   args        Scanner scan   new Scanner System in       System out println  Enter size of Array        int size   scan nextInt        int   arr   new int size       for  int i   0  i  lt  size  i              arr i    scan nextInt              System out println  second highest element     getSecondHighest arr       public static int getSecondHighest int arr          int firstHighest   arr 0       int secondHighest   arr 0       for  int i   0  i  lt  arr length  i              if  arr i   gt  firstHighest                secondHighest   firstHighest              firstHighest   arr i             else if  arr i   gt  secondHighest                secondHighest   arr i                       return secondHighest

User · Answer

private static int SecondBiggest int   vector        if  vector    null                throw new ArgumentNullException  vector              if  vector Length  lt  2                return int MinValue             int max1   vector 0       int max2   vector 1       for  int i   2  i  lt  vector Length    i                if  max1  gt  max2  amp  amp  max1    vector i                         max2   Math Max max2  vector i                      else if  max2    vector i                         max1   Math Max max1  vector i                        return Math Min max1  max2       This treats duplicates as the same number   You can change the condition checks if you want to all the biggest and the second biggest to be duplicates

User · Answer

Its very easy to get the 2nd highest element in an array  I ve shows below for all your reference  Hope this will be helpful   import java util Arrays   public class Testdemo       public static void main String   args        int   numbers    1  5  4  2  8  1  1  6  7  8  9       Arrays sort numbers       System out println  The second Higest Element      numbers numbers length-2              Ans - The second Higest Element  8

User · Answer

If you want to 2nd highest and highest number index in array then      public class Scoller student        public static void main String   args            System out println   t t tEnter No  of Student n            Scanner scan   new Scanner System in           int student no   scan nextInt                Marks Array                  int   marks          marks   new int student no               Student name array              String   names          names   new String student no           int max   0          int sec   max          for  int i   0  i  lt  student no  i                  System out println   t t tEnter Student Name of id       i                      names i    scan next                System out println   t t tEnter Student Score of id       i      n                 marks i    scan nextInt                if  marks max   lt  marks i                     sec   max                  max   i                else if  marks sec   lt  marks i   amp  amp  marks max     marks i                     sec   i                                   if  max    sec                sec   1              for  int i   1  i  lt  student no  i                      if  marks sec   lt  marks i                         sec   i                                                     System out println   t t tHigherst score id         max       Name                     names max        Max mark         marks max         n            System out println   t t tSecond Higherst score id         sec       Name                     names sec        Max mark         marks sec         n

User · Answer

You can find Largest and Third largest number of unsorted array as well    public class ThirdLargestNumber           public static void main String   args                int arr       220  200  100  100  300  600  50  5000  125  785                int first   0  second   0  third   0  firstTemp   0  secondTemp   0              for  int i   0  i  lt   9                                           Length of array-1  You can use here length                                        property of java array instead of hard coded                                        value                                          i                      if  arr i     first                        continue                                    if  arr i   gt  first                        firstTemp   first                      secondTemp   second                      first   arr i                       second   firstTemp                      if  secondTemp  gt  third                            third   secondTemp                                          else                       if   arr i     second      arr i      first                            continue                                            if   arr i   gt  second   amp  amp   arr i    lt  first                            secondTemp   second                          second   arr i                           if  secondTemp  gt  third                                third   secondTemp                                                  else                           if  arr i   gt  third                                third   arr i                                                                                                  System out println  Third largest number      third               System out println  Second largest number      second                  System out println  Largest number      first

User · Answer

Initialize these to the smallest value possible int highest   Integer MIN VALUE  int secondHighest   Integer MIN VALUE      Loop over the array for  int i   0  i  lt  array Length  i              If we ve found a new highest number        if  array i   gt  highest                   shift the current highest number to second highest         secondHighest   highest                 and set the new highest          highest   array i         else if  array i   gt  secondHighest             Just replace the second highest         secondHighest   array i               After exiting the loop  secondHighest now represents the second    largest value in the array   Edit  Whoops  Thanks for pointing out my mistake  guys  Fixed now

User · Answer

public class secondLargestElement        public static void main String   args                 int   a1  1 0           secondHigh a1              public static void secondHigh int   arr                try                       int highest sec high              highest arr 0               sec high arr 1                    for int i 1 i lt arr length i                                          if arr i  gt highest                                                           sec high highest                          highest arr i                                              else                         The first condition before the    is to make sure that second highest is not actually same as the highest   think                             about  5 4 5   you don t want the last  5 to be reported as the sec high                            The other half after    says if the first two elements are same then also replace the sec high with incoming integer                            Think about  5 5 4                      if arr i  gt sec high  amp  amp  arr i  lt highest    highest  sec high                          sec high arr i                                   System out println  high   highest   sec  sec high               if highest  sec high                  System out println  All the elements in the input array are same                 else                  System out println  The second highest element in the array is    sec high                        catch ArrayIndexOutOfBoundsException e                    System out println  Not enough elements in the array              e printStackTrace

User · Answer

I am giving solution that s not in JAVA program  written in JavaScript   but it takes o n 2  iteration to find the highest and second highest number  Working fiddler link Fiddler link   var num  1020215 2000 35 2 54546 456 2 2345 24 545 132 5469 25653 0 2315648978523   var j num length-1  var firstHighest 0 seoncdHighest 0  num 0   gt num num length-1   firstHighest num 0  seoncdHighest num num length-1    firstHighest num num length-1     seoncdHighest num 0    j--  for var i 1 i lt  num length 2 i   j--       if num i   lt  num j                   if firstHighest  lt  num j              seoncdHighest firstHighest             firstHighest  num j                          else if seoncdHighest  lt  num j                     seoncdHighest  num j                         else          if firstHighest  lt  num i                       seoncdHighest firstHighest             firstHighest  num i                    else if seoncdHighest  lt  num i                  seoncdHighest  num i

User · Answer

Second Largest in O n 2   public class SecMaxNum           second Largest number with O n 2                  author Rohan Kamat         Date Feb 04  2016             public static void main String   args            int   input     1  5  10  11  11  4  2  8  1  8  9  8            int large   0  second   0           for  int i   0  i  lt  input length - 1  i   i   2                   System out println i               int fist   input i               int sec   input i   1               if  sec  gt   fist                    int temp   fist                  fist   sec                  sec   temp                            if  fist  gt   second                    if  fist  gt   large                        large   fist                    else                       second   fist                                                if  sec  gt   second                    if  sec  gt   large                        large   sec                    else                       second   sec

User · Answer

Function to print the second largest elements        void print2largest int arr    int arr size           int i  first  second         There should be atleast two elements       if  arr size  lt  2           printf   Invalid Input         return            first   second   INT MIN     for  i   0  i  lt  arr size   i                 If current element is smaller than first        then update both first and second        if  arr i   gt  first                second   first          first   arr i                 If arr i  is in between first and         second then update second         else if  arr i   gt  second  amp  amp  arr i     first          second   arr i           if  second    INT MIN      printf  There is no second largest elementn        else     printf  The second largest element is  dn   second

User · Answer

public class SecondHighInIntArray    public static void main String   args        int   intArray new int   2 2 1                  2 2 1 12 3 7 9 -1 -5 7       int secHigh findSecHigh intArray       System out println secHigh      private static int findSecHigh int   intArray         int highest Integer MIN VALUE      int sechighest Integer MIN VALUE      int len intArray length      for int i 0 i lt len i                  if intArray i  gt highest                        sechighest highest              highest intArray i               continue                     if intArray i  lt highest  amp  amp  intArray i  gt sechighest                        sechighest intArray i               continue                        return sechighest

User · Answer

I will propose even shorter and simplest answer to the problem and it contains 2 lines of code in the method  import java util Arrays is required        public static int secMax int   num       Arrays sort num       temp   num num length-2        return temp

User · Answer

The simplest way is -   public class SecondLargest       public static void main String   args            int   arr     1  2  5  6  3             int first   Integer MIN VALUE          int second   Integer MIN VALUE          for  int i   0  i  lt  arr length  i                     If current element is smaller than first then update both first                and second             if  arr i   gt  first                    second   first                  first   arr i                                If arr i  is in between first and second then update second             else if  arr i   gt  second  amp  amp  arr i     first                    second   arr i

User · Answer

static int secondLargest int   input       int largest   secondlargest       if input 0  gt input 1                 largest input 0           secondlargest   input 1             else               secondlargest   input 0           largest  input 1             for int i  2  i lt input length i             if input i  gt largest                        secondlargest    largest              largest   input i                     else if input i  gt secondlargest               secondlargest   input i                        return secondlargest

User · Answer

public static int secondLargest int   input                int largest secondLargest               if input 0   gt  input 1                     largest   input 0                   secondLargest   input 1                             else                   largest   input 1                   secondLargest   input 0                              for int i   2  i  lt  input length  i                      if  input i   lt   largest   amp  amp  input i   gt  secondLargest                        secondLargest   input i                                      if input i   gt  largest                        secondLargest   largest                      largest   input i                                                return secondLargest

User · Answer

public class SecondLargestNumber     public static void main String   args          int   var  -11 -11 -11 -11 115 -11 -9       int largest   0      int secLargest   0      if var length    1              largest   var 0         secLargest   var 0             else if var length  gt  1              largest  var 0         secLargest   var 1         for int i 1 i lt var length i                    if secLargest  largest                      if var i  gt largest                           secLargest   largest              largest   var i                         else if var i  gt secLargest  amp  amp  var i     largest                          secLargest  var i                                 else                     if var i  gt largest                         secLargest   largest             largest   var i                         else                        secLargest   var i                                       System out println  Largest    largest   Second Largest    secLargest

User · Answer

Scanner sc   new Scanner System in    System out println   n number of input sets      int value sc nextInt    System out println   n input sets      int   inputset    inputset   new int value   for int i 0 i lt value i          inputset i  sc nextInt      int maxvalue inputset 0   int secondval inputset 0   for int i 1 i lt value i          if inputset i  gt maxvalue               maxvalue inputset i           for int i 1 i lt value i          if inputset i  gt secondval  amp  amp  inputset i  lt maxvalue                secondval inputset i           System out println   n maxvalue   maxvalue   System out println   n secondmaxvalue   secondval

User · Answer

private static void returnSecondHighetsNumber int   a             int firstHighest 0           int secondHighest 0           if a 0  gt  a 1                  firstHighest a 0                secondHighest a 1             else                firstHighest a 1                secondHighest a 0                       for  int i   2  i  lt  a length  i                   if a i   gt  firstHighest                     secondHighest firstHighest                   firstHighest a i                               else if a i  gt  secondHighest                     secondHighest a i                                      System out println firstHighest  quot --- quot  secondHighest

User · Answer

The answers I saw wont work if there are two same largest numbers like the below example           int   randomIntegers     1  5  4  2  8  1  8  9 9            SortedSet lt Integer gt  set   new TreeSet lt Integer gt             for  int i  randomIntegers                set add i                        Remove the maximum value  print the largest remaining item         set remove set last             System out println set last       I have removed it from the Set not from the Array

User · Answer

Problem  The problem is to get the second largest array element    Observation  Second largest number is defined as the number that has the minimum difference when subtracted from the maximum element in the array   Solution  This is a two pass solution  First pass is to find the maximum number  Second pass is to find the element that has minimum difference with the maximum element as compared to other array elements  Example  In the array  2  3  6  6  5  maximum   6 and second maximum   5   since it has the minimum difference to the maximum element 6 - 5   1 the solution for second largest   5  function printSecondMax myArray      var x  max   myArray 0        Find maximum element    for x in myArray        if max  lt  myArray x            max   myArray x                var secondMax   myArray 0   diff   max - secondMax       Find second max  an element that has min diff with the max   for x in myArray       if diff    0  amp  amp   max - myArray x      0  amp  amp  diff  gt   max - myArray x             secondMax   myArray x           diff   max - secondMax              console log secondMax       Complexity   O n   This is the simplest way to do this   For finding maximum element even more efficiently one can look into max heap  a call to max-heapify will take O log n  time to find the max and then pop-ing the top element gives maximum  To get the second maximum  max-heapify after pop-ing the top and keep pop-ing till you get a number that is less than maximum  That will be the second maximum  This solution has O n log n  complexity

User · Answer

I m not convinced that doing what you did fixes the problem  I think it masks yet another problem in your logic  To find the second highest is actually quite simple    static int secondHighest int    nums        int high1   Integer MIN VALUE      int high2   Integer MIN VALUE      for  int num   nums          if  num  gt  high1            high2   high1          high1   num          else if  num  gt  high2            high2   num                    return high2       This is O N  in one pass  If you want to accept ties  then change to if  num  gt   high1   but as it is  it will return Integer MIN VALUE if there aren t at least 2 elements in the array  It will also return Integer MIN VALUE if the array contains only the same number

[java] Finding the second highest number in array

Examples related to java