#include <iostream>
#include <sstream>
using namespace std;
int main()
{
string s;
getline(cin, s);
stringstream ssin(s);
string s2, r;
int t = 0;
while (ssin >> s2)
{
if (s2.back() == '.') s2.pop_back();
if (s2.size() > t)
{
t = s2.size();
r = s2;
}
}
cout << r <<endl;
return 0;
}