用C++的string类

#include <iostream>
#include <string>

using namespace std;

int main() 
{
    string ss, ans;
    int end = 0;
    while (1)
    {
        cin >> ss;
        if (ss[ss.length() - 1] == '.') end = 1;

        int ss_len = ss.length();
        if (end) ss_len -- ;

        if (ss_len > ans.length()) ans = ss; 

        if (end) break;

    }

    for (int i = 0; i < ans.length(); i ++ )
    {
        if (ans[i] == '.' && i == ans.length() - 1) continue;
        cout << ans[i];
    }

    return 0;
}