minimum_difference_in_array_of_unique_integers_v1.c

/*

    minimum_difference_in_array_of_unique_integers_v1.c

    Task:
    https://web.facebook.com/photo/?fbid=350432899315771&set=gm.3403903939630572

    https://www.geeksforgeeks.org/find-minimum-difference-pair/


    You can find all my C programs at Dragan Milicev's pastebin:

    https://pastebin.com/u/dmilicev

*/

#include <stdio.h>
#include <limits.h>     // for INT_MAX

// Returns minimum difference between any pair
int findMinDiff(int arr[], int n, int *first, int *second)
{
    int i, j, diff = INT_MAX;   // Initialize difference as infinite

    // Find the min diff by comparing difference of all possible pairs in given array
    for (i=0; i<n-1; i++)
        for (j=i+1; j<n; j++)
            if (abs(arr[i] - arr[j]) < diff)
            {
                diff = abs(arr[i] - arr[j]);

                if(arr[i] < arr[j])
                {
                    *first = arr[i];
                    *second = arr[j];
                }
                else
                {
                    *first = arr[j];
                    *second = arr[i];
                }

                printf("\n diff = %d \t first = %d \t second = %d\n", diff, *first, *second);
            }

    return diff;                // Return min diff
}

int main(void)
{
    int arr[] = {67,33,45,2,89,120,52,309,21,101,190,567,985,774,8,631,99,1234,15,590};
    int first=1, second=2;
    int diff;
    int n = sizeof(arr)/sizeof(arr[0]);

    diff=findMinDiff(arr, n, &first, &second);

/*
    // Be careful:
    // Calling the findMinDiff() function inside the printf() function does not work well !!!
    printf("\n Minimum difference is %d between %d and %d \n",
            findMinDiff(arr, n, &first, &second), first, second );
*/
    printf("\n Minimum difference among %d unique integers is %d between %d and %d \n",
            n, diff, first, second );

    return 0;

} // main()