#include <bits/stdc++.h>   using namespace std;   long long n, m, k, x, y, z;   int main() {     cin >> n >> k >> m;     if (m <= k)       cout << m << endl;     else if (m <= n)       cout << k << endl;     else {       long long tmp = n + k;       cout << tmp - m << endl;     }     return 0;   }   