[c++] Find largest and smallest number in an array

int main () //start of main fcn
{

    int values[ 20 ]; //delcares array and how many elements
    int small,big; //declares integer
     for ( int i = 0; i < 20; i++ ) //counts to 20 and prompts user for value and stores it
    {
        cout << "Enter value " << i << ": ";
        cin >> values[i];
    }
    big=small=values[0]; //assigns element to be highest or lowest value
    for (int i = 0; i < 20; i++) //works out bigggest number
    {
        if(values[i]>big) //compare biggest value with current element
        {
            big=values[i];
        }
         if(values[i]<small) //compares smallest value with current element
        {
            small=values[i];
        }
    }
     cout << "The biggest number is " << big << endl; //prints outs biggest no
    cout << "The smallest number is " << small << endl; //prints out smalles no
}