#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: lijinkai
	Language: C++
	Result: Accepted
	Time:11 ms
	Memory:2072 kb
****************************************************************/