#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
using PL = pair<ll, ll>;
// Welcome to my source code!

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