#include<bits/stdc++.h>
using namespace std;
int main()
{
    int i,n=0;
    char a[256],s[256],d[256]={'\0'};
    gets(a);
    for(i=0;i<strlen(a);i++){
        if(a[i]!=' '){
            s[n]=a[i];
            n++;
            if(a[i+1]==' '||a[i+1]=='\0'){
                s[n]='\0';
                if(strlen(s)>strlen(d)){
                    strcpy(d,s);
                }
                n=0;
            }
        }   
    }
    cout<<d;
    return 0;
}
/**************************************************************
	Problem: 1107
	User: wengsihan
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2076 kb
****************************************************************/