文件目录

#include <iostream>
#include <sstream>
using namespace std;
int main()
{
    string s, k;
    getline(cin, s);
    s = s.substr(0, s.size() - 1);
    istringstream ss(s);
    string mas = "";
    int mad = 0;
    while (ss >> k)
    {
        if (k.size() > mad)
        {
            mad = k.size();
            mas = k;
        }
    }
    cout << mas;
    return 0;
}