#include<bits/stdc++.h>
using namespace std;
string a, b;
int len = 0;
int main() {
    while (cin >> a) {
        if (a.back() == '.') a.pop_back();
        if (a.length() > len) {
            b = a;
            len = a.length();
        }
    }
    cout << b;
}