process.stdin.resume();
process.stdin.setEncoding('ascii');

var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;

process.stdin.on('data', function (data) {
    input_stdin += data;
});

process.stdin.on('end', function () {
    input_stdin_array = input_stdin.split("\n");
    main();    
});

function readLine() {
    return input_stdin_array[input_currentline++];
}

/////////////// ignore above this line ////////////////////

function main() {
    var n_temp = readLine().split(' ');
    var n = parseInt(n_temp[0]);
    var q = parseInt(n_temp[1]);
    var s = readLine();
    var a = [];
    var type, i, j, t, c;
    for(var a0 = 0; a0 < q; a0++){
        n_temp = readLine().split(' ');
        type = parseInt(n_temp[0]);
        if (type == 2) {
            i = parseInt(n_temp[1]);
            j = parseInt(n_temp[2]);
        } else {
            i = parseInt(n_temp[1]);
            j = parseInt(n_temp[2]);
            t = parseInt(n_temp[3]);            
            
            for(var k = i; k <= j; k++)
                for (var l = 0; l < t % 26; l++) {
                    console.error(s[k]);
                    s = s.replaceAt(k, nextChar(s[k]));
                }

            continue;
        } 

        // do stuff with type 2
        for(var k = 0; k < 26; k++) a[k] = 0;
        for(var k = i; k <= j; k++)  a[s.charCodeAt(k) - 97]++; //console.error(s.charCodeAt(k));
        //console.error(a);
        c = 0;
        for(var k = 0; k < 26; k++) {
             c += a[k]*a[k]; 

         }
        console.log(c);
            
            
        }
        
        
    console.error(s);

}

String.prototype.replaceAt=function(index, character) {
    return this.substr(0, index) + character + this.substr(index+character.length);
}

function nextChar(c) {
    return String.fromCharCode(c.charCodeAt(0) + 1);
}