[javascript] Optimum way to compare strings in JavaScript?

I am trying to optimize a function which does binary search of strings in JavaScript.

Binary search requires you to know whether the key is == the pivot or < the pivot.

But this requires two string comparisons in JavaScript, unlike in C like languages which have the strcmp() function that returns three values (-1, 0, +1) for (less than, equal, greater than).

Is there such a native function in JavaScript, that can return a ternary value so that just one comparison is required in each iteration of the binary search?

This question is related to javascript string optimization comparison binary-search

The answer is


Well in JavaScript you can check two strings for values same as integers so yo can do this:

  • "A" < "B"
  • "A" == "B"
  • "A" > "B"

And therefore you can make your own function that checks strings the same way as the strcmp().

So this would be the function that does the same:

function strcmp(a, b)
{   
    return (a<b?-1:(a>b?1:0));  
}

You can use the comparison operators to compare strings. A strcmp function could be defined like this:

function strcmp(a, b) {
    if (a.toString() < b.toString()) return -1;
    if (a.toString() > b.toString()) return 1;
    return 0;
}

Edit    Here’s a string comparison function that takes at most min { length(a), length(b) } comparisons to tell how two strings relate to each other:

function strcmp(a, b) {
    a = a.toString(), b = b.toString();
    for (var i=0,n=Math.max(a.length, b.length); i<n && a.charAt(i) === b.charAt(i); ++i);
    if (i === n) return 0;
    return a.charAt(i) > b.charAt(i) ? -1 : 1;
}

Examples related to javascript

need to add a class to an element How to make a variable accessible outside a function? Hide Signs that Meteor.js was Used How to create a showdown.js markdown extension Please help me convert this script to a simple image slider Highlight Anchor Links when user manually scrolls? Summing radio input values How to execute an action before close metro app WinJS javascript, for loop defines a dynamic variable name Getting all files in directory with ajax

Examples related to string

How to split a string in two and store it in a field String method cannot be found in a main class method Kotlin - How to correctly concatenate a String Replacing a character from a certain index Remove quotes from String in Python Detect whether a Python string is a number or a letter How does String substring work in Swift How does String.Index work in Swift swift 3.0 Data to String? How to parse JSON string in Typescript

Examples related to optimization

Why does C++ code for testing the Collatz conjecture run faster than hand-written assembly? Measuring execution time of a function in C++ GROUP BY having MAX date How to efficiently remove duplicates from an array without using Set Storing JSON in database vs. having a new column for each key Read file As String How to write a large buffer into a binary file in C++, fast? Is optimisation level -O3 dangerous in g++? Why is processing a sorted array faster than processing an unsorted array? MySQL my.cnf performance tuning recommendations

Examples related to comparison

Wildcard string comparison in Javascript How to compare two JSON objects with the same elements in a different order equal? Comparing strings, c++ Char Comparison in C bash string compare to multiple correct values Comparing two hashmaps for equal values and same key sets? Comparing boxed Long values 127 and 128 Compare two files report difference in python How do I fix this "TypeError: 'str' object is not callable" error? Compare cell contents against string in Excel how to calculate binary search complexity Find kth smallest element in a binary search tree in Optimum way Optimum way to compare strings in JavaScript? What is the difference between Linear search and Binary search? Binary search (bisection) in Python