#include <bits/stdc++.h>
using namespace std;
string itosm(long long x) {
  if (x == 0) return "0";
  string ans = "";
  while (x > 0) {
    ans += ((x % 10) + '0');
    x /= 10;
  }
  reverse(ans.begin(), ans.end());
  return ans;
}
long long stoim(string str) {
  long long ans = 0;
  long long k = 1;
  for (int i = str.length() - 1; i >= 0; i--) {
    ans += (str[i] - '0') * k;
    k *= 10;
  }
  return ans;
}
const long long infll = 1e18 + 3;
const int inf = 1009000999;
const double eps = 1e-7;
const int maxn = 1e5 + 777;
const int baseint = 1000200013;
const long long basell = 1e18 + 3;
const long double PI = acos(-1.0);
const long long mod = 1e9 + 7;
void solve() {
  int n, k, t;
  cin >> n >> k >> t;
  if (t <= k) {
    cout << t;
  } else if (t <= n) {
    cout << k;
  } else {
    cout << n + k - t;
  }
}
int main() {
  srand(time(0));
  ios_base::sync_with_stdio(0);
  ;
  solve();
  return 0;
}
