#include <iostream>
using namespace std;

int main()
{
	int a[30] = { 0 };

	while (true)
	{
		char ch = 0;
		cin >> ch;
		if (!std::cin.good()) break;
		ch = tolower(ch);
		a[ch - 'a']++;
	}

	for (int i = 0; i < 26; i++) {
		char ch = 'a' + i;
		cout << ch << " : " << a[i] << endl;
	}

	return 0;
}
