#!/bin/python
def all_palindromes(string):
    return len(string)


def shift(char,dist):
    return chr(((ord(char)-97 + dist) % 26)+97)

import sys

n,q = raw_input().strip().split(' ')
n,q = [int(n),int(q)]
s = raw_input().strip()
for a0 in xrange(q):
    query = raw_input().strip().split(' ')
    if (int(query[0]) == 1):
        start = int(query[1])
        end = int(query[2])
        d = int(query[3])
        new_s = s[0:start]
        for i in range(start,end+1):
            new_s = new_s + shift(s[i],d)
        s = new_s + s[end+1:]
    else:
        start = int(query[1])
        end = int(query[2])
        print all_palindromes(s[start:end+1])