var input = require('fs').readFileSync('/dev/stdin', 'utf8');
input = input.trim().toLowerCase();
input = input.replace(/\s+/g,"");
var alpha = "abcdefghijklmnopqrstuvwxyz";
for(var i=0;i<alpha.length;i++){
    var count = 0;
    for(var j=0;j<input.length;j++){
        if(alpha[i] === input[j]){
            count++;
        }
    }
    console.log(alpha[i] + " : " + count);
}

