#include <iostream>
using namespace std;

int min4(int a, int b, int c, int d) {
	int e = min(a, b);
	int f = min(c, d);
	return min(e, f);
}

int main() {
	
	int a, b, c, d;
	cin >> a >> b >> c >> d;
	cout << min4(a, b, c, d);
	
	return 0;
}