#include <iostream>
#include <string>
using namespace std;

int main() {
    string s;
    int a[26];
    for (int j = 0; j < 26; ++j) {
        a[j] = 0;
    }
    getline(cin,s);
    while (s!="") {

        for (int i = 0; i < s.length(); ++i) {
            switch (s[i]) {
                case 'a':
                case 'A':
                    a[0]++;
                    break;
                case 'b':
                case 'B':
                    a[1]++;
                    break;
                case 'c':
                case 'C':
                    a[2]++;
                    break;
                case 'd':
                case 'D':
                    a[3]++;
                    break;
                case 'e':
                case 'E':
                    a[4]++;
                    break;
                case 'f':
                case 'F':
                    a[5]++;
                    break;
                case 'g':
                case 'G':
                    a[6]++;
                    break;
                case 'h':
                case 'H':
                    a[7]++;
                    break;
                case 'i':
                case 'I':
                    a[8]++;
                    break;
                case 'j':
                case 'J':
                    a[9]++;
                    break;
                case 'k':
                case 'K':
                    a[10]++;
                    break;
                case 'l':
                case 'L':
                    a[11]++;
                    break;
                case 'm':
                case 'M':
                    a[12]++;
                    break;
                case 'n':
                case 'N':
                    a[13]++;
                    break;
                case 'o':
                case 'O':
                    a[14]++;
                    break;
                case 'p':
                case 'P':
                    a[15]++;
                    break;
                case 'q':
                case 'Q':
                    a[16]++;
                    break;
                case 'r':
                case 'R':
                    a[17]++;
                    break;
                case 's':
                case 'S':
                    a[18]++;
                    break;
                case 't':
                case 'T':
                    a[19]++;
                    break;
                case 'u':
                case 'U':
                    a[20]++;
                    break;
                case 'v':
                case 'V':
                    a[21]++;
                    break;
                case 'w':
                case 'W':
                    a[22]++;
                    break;
                case 'x':
                case 'X':
                    a[23]++;
                    break;
                case 'y':
                case 'Y':
                    a[24]++;
                    break;
                case 'z':
                case 'Z':
                    a[25]++;
                    break;
                default:
                    break;
            }
        }
        getline(cin,s);
    }
    for (int k = 0; k < 26; ++k) {
        char c = static_cast<char>(k + 97);
        cout<<c<<" : "<<a[k]<<endl;
    }
    return 0;
}


Measured memory_bytes: 3152