#include<bits/stdc++.h>
using namespace std;
int main(){
	string s,mx="",a;
	getline(cin,s);
	for(int i=0;i<s.size();i++){
		if(s[i]!=' ') a+=s[i];
		else if(mx.size()<a.size()){
			mx=a;
			a=""; 
		}
	}
	cout<<mx;
    return 0;
}
/**************************************************************
	Problem: 1107
	User: panyuchen
	Language: C++
	Result: Wrong Answer
****************************************************************/