#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}

int64_t rll() {
	long long n;
	scanf("%lld", &n);
	return n;
}

int main() {
	int64_t x = rll(), y = rll(), z = rll();
	int64_t cnt = z;
	if (x <= z) cnt--;
	if (y <= z) cnt--;
	std::cout << cnt << std::endl;
	return 0;
}