Count the total number of duplicate elements in an array with C. 

Input

Input array elements: 1 2 3 4 5 1 2 4 5 6

Output

Total number of duplicate elements = 4


#include <stdio.h>

int main()
{
    int arr[100];
    int i, j, size, count = 0;

    /* Input size of array */
    printf("Enter size of the array : ");
    scanf("%d", &size);

    /* Input elements in array */
    printf("Enter elements in array : ");
    for (i = 0; i < size; i++)
    {
        scanf("%d", &arr[i]);
    }
    /*
     * Find all duplicate elements in array
     */
    for (i = 0; i < size; i++)
    {
        for (j = i + 1; j < size; j++)
        {
            /* If duplicate found then increment count by 1 */
            if (arr[i] == arr[j])
            {
                count++;
                break;
            }
        }
    }

    printf("\nTotal number of duplicate elements found in array = %d", count);

    return 0;
}

Output

Enter size of the array : 10 
Enter elements in array : 1 2 3 4 5 1 2 4 5 6

Total number of duplicate elements found in array = 4