#include <iostream>
#include <algorithm>
using namespace std;

int x, y, z;

int main() {
	cin >> x >> y >> z;
	
	int ans = 0;
	for (int i = 0; i <= z; i++) {
		int res = min(x + i, y + z - i);
		ans = max(ans, res);
	}
	cout << ans << endl;
	return 0;
}