Untitled

include <iostream>
using namespace std;
int main()
{
	int a, b, c, d, g = 0;
	cin >> a >> b >> c >> d;
	if (a == b || a == c || a == d) g += 1;
	if (b == c || b == d) g += 1;
	if (c == d) g += 1;
	cout << g;
}