#include <cstdlib>
#include <cctype>
#include <cstring>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <vector>
#include <string>
#include <iostream>
#include <sstream>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <fstream>
#include <numeric>
#include <iomanip>
#include <bitset>
#include <list>
#include <stdexcept>
#include <functional>
#include <utility>
#include <ctime>
#include <valarray>
#include <random>
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
#define MEM(a,b) memset((a),(b),sizeof(a))
const LL INF = 1e9 + 7;
const int N = 2e5 + 10;

int main()
{
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w",d stdout);
	LL x, y, z;
	cin >> x >> y >> z;
	LL ans = z;
	if (x <= z) ans--;
	if (y <= z) ans--;
	cout << ans << endl;
	return 0;
}