#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vl = vector<ll>;
#define rep(i, n) for(ll i = 0;i < n;i++)
#define all(i) i.begin(), i.end()
template<class T, class U> bool cmax(T& a, U b) { if (a<b) {a = b; return true;} else return false; }
template<class T, class U> bool cmin(T& a, U b) { if (a>b) {a = b; return true;} else return false; }

int main() {
  cin.tie(0); ios::sync_with_stdio(false);

  ll x, y, z;
  cin >> x >> y >> z;
  ll ans = z;
  if (x <= z) ans--;
  if (y <= z) ans--;
  cout << ans << endl;
}