#include <cstdio>
#include <cstdlib>
#include <cstddef>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <string>
#include <iostream>
#include <iomanip>
#include <numeric>
#define L64 long long
#define UL64 unsigned long long
#define MOD (1000000007LL)

int main(void)
{
  L64 a, b, c;
  std::cin >> a >> b >> c;
  L64 r = c;
  if(a <= c) r--;
  if(b <= c) r--;
  std::cout << r << std::endl;
}