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

int main() {
	const set<char> required{'a','e','i','o','u'};
	set <char> seen;
	map<char,int> chr2cnt;
	while (true)
	{
		char c = 'a'+ (rand()%26);
		if (required.count(c))
		{
			seen.insert(c);
			chr2cnt[c]++;
			if (seen.size()==required.size())
			{
				for (const auto& kvp: chr2cnt)
				{
					cout << kvp.first << ": " << kvp.second << endl;
				}
				break;
			}
		}
	}
	return 0;
}