228A - Is your horseshoe on the other hoof?

#include <cmath>#include <cstdio>#include <cstdlib>#include <cstring>#include <iostream>#include <string>#include <vector>#include <queue>#include <algorithm>using namespace std;int main() {    int s[4];    int ans = 0;    cin >> s[0] >> s[1] >> s[2] >> s[3];    sort(s, s + 4);    for(int i = 0; i < 3; ++i) {        if(s[i] == s[i+1]) {            ans++;        }    }    cout << ans << endl;    return 0;}