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

/**************************************************************
	Problem: 1305
	User: ccf
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/