#include <stdio.h>

#define NUM 5

int main(void) {
    double a[NUM] = {1.0, 1.2, 1.3, 1.0, 1.0};
    int count = 0;

    for (int x = 0; x < NUM; x++) {
        for (int y = x + 1; y < NUM; y++) {
            if (a[x] == a[y]) {
                count++;
            }
        }
    }

    printf("%d\n", count);

    return 0;
}