#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  ll x, y, z;
  cin >> x >> y >> z;
  ll ans = z;
  if (x <= z) ans--;
  if (y <= z) ans--;
  cout << ans << endl;
  return 0;
}