#include <iostream>
using namespace std;

int main() {
	int a1, a2, a3, a4, c;
	cin >> a1 >> a2 >> a3 >> a4;
	c = a1;
	if (c < a2) {
		c = a2;
	}
	if (c < a3) {
		c = a3;
	}
	if (c < a4) {
		c = a4;
	}
	cout << c;
	return 0;
}

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