#include <stdio.h>

#define NUM 5

int main(void)
{
double a[NUM];
int i, j;
int count = 0;

for (i = 0; i < NUM; i=i+1)
{
scanf("%lf", &a[i]);
}

for (i = 0; i < NUM; i=i+1)
{
for (j = i + 1; j < NUM; j=j+1)
{
if (a[i] == a[j]) {
count=count+1;
}
}
}

printf("%d", count);
return 0;
}