vowel counting

#include <iostream>
#include <map>
#include <algorithm>
using namespace std;

int main(int argc, char **argv)
{
    setlocale( LC_ALL,"Russian" );

    multimap<size_t, string> words;

    cout << "Введите слова (ctrl+z для остановки): " << endl;
    for(string word;;)
    {
        cin >> word;

        if (cin.eof())
            break;

        size_t vowel_count = count_if(word.begin(), word.end(),
            [](char c){ return string("aeiou").find_first_of(c) != string::npos; });

        words.insert(make_pair(vowel_count, word));
    }

    if (words.size() != 0)
    {
        double percent = (100.0*words.rbegin()->first) / words.rbegin()->second.size();
        cout << "word: " << words.rbegin()->second << endl;
        cout << "percent: " << percent << endl;
    }

    system("pause");
    return 0;
}