#include <bits/stdc++.h>
using namespace std;
int main(){
	int a,b,c,d,t;
	cin>>a>>b>>c>>d;
	if(a<b) swap (a,b);
	if(a<c) swap (a,c);
	if(a<d) swap (a,d);
	cout<<a;
	return 0;
	
	}

/**************************************************************
	Problem: 1305
	User: ljl2
	Language: C++
	Result: Accepted
	Time:11 ms
	Memory:2072 kb
****************************************************************/