#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(a!=""&&a.size()>mx.size()){
                mx=a;}
            a=""; 
        }
    }
    if(a.size()>mx.size()){
        mx=a;
}
    cout<<mx;
}
/**************************************************************
	Problem: 1107
	User: linzihang
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/