# input
import sys
input = sys.stdin.readline
II = lambda : int(input())
MI = lambda : map(int, input().split())
LI = lambda : [int(a) for a in input().split()]
SI = lambda : input().rstrip()
LLI = lambda n : [[int(a) for a in input().split()] for _ in range(n)]
LSI = lambda n : [input().rstrip() for _ in range(n)]
MI_1 = lambda : map(lambda x:int(x)-1, input().split())
LI_1 = lambda : [int(a)-1 for a in input().split()]

def graph(n:int, m:int, dir:bool=False, index:int=-1) -> list[set[int]]:
    edge = [set() for i in range(n+1+index)]
    for _ in range(m):
        a,b = map(int, input().split())
        a += index
        b += index
        edge[a].add(b)
        if not dir:
            edge[b].add(a)
    return edge

def graph_w(n:int, m:int, dir:bool=False, index:int=-1) -> list[set[tuple]]:
    edge = [set() for i in range(n+1+index)]
    for _ in range(m):
        a,b,c = map(int, input().split())
        a += index
        b += index
        edge[a].add((b,c))
        if not dir:
            edge[b].add((a,c))
    return edge

mod = 998244353
inf = 1001001001001001001
ordalp = lambda s : ord(s)-65 if s.isupper() else ord(s)-97
ordallalp = lambda s : ord(s)-39 if s.isupper() else ord(s)-97
yes = lambda : print("Yes")
no = lambda : print("No")
yn = lambda flag : print("Yes" if flag else "No")
def acc(a:list[int]):
    sa = [0]*(len(a)+1)
    for i in range(len(a)):
        sa[i+1] = a[i] + sa[i]
    return sa

prinf = lambda ans : print(ans if ans < 1000001001001001001 else -1)
alplow = "abcdefghijklmnopqrstuvwxyz"
alpup = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
alpall = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
URDL = {'U':(-1,0), 'R':(0,1), 'D':(1,0), 'L':(0,-1)}
DIR_4 = [[-1,0],[0,1],[1,0],[0,-1]]
DIR_8 = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]]
DIR_BISHOP = [[-1,1],[1,1],[1,-1],[-1,-1]]
prime60 = [2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59]
sys.set_int_max_str_digits(0)
# sys.setrecursionlimit(10**6)
# import pypyjit
# pypyjit.set_param('max_unroll_recursion=-1')

from collections import defaultdict,deque
from heapq import heappop,heappush
from bisect import bisect_left,bisect_right
DD = defaultdict
BSL = bisect_left
BSR = bisect_right

class Dynamic_BIT:
    def __init__(self, n):
        self.n = n
        self.data = dict()
    
    def add(self, p, x):
        p += 1
        while p < self.n:
            if p in self.data:
                self.data[p] += x
            else:
                self.data[p] = x
            p += p& -p
    
    def sum0(self, r):
        s = 0
        while r > 0:
            if r in self.data:
                s += self.data[r]
            r -= r& -r
        return s
    
    def sum(self, l, r):
        return self.sum0(r) - self.sum0(l)
    
    def get(self, p):
        return self.sum0(p+1) - self.sum0(p)
    
    def __str__(self):
        return str([self.get(i) for i in range(self.n)])


n, q = MI()
t = list(map(ordalp, SI()))

siz = 26 * 26 * 26
c = [Dynamic_BIT(n + 10) for i in range(siz)]
s = [Dynamic_BIT(n + 10) for i in range(siz)]

a = [0] * n
for i in range(2, n):
    for j in range(-2, 1):
        a[i] *= 26
        a[i] += t[i+j]
    c[a[i]].add(i, 1)
    s[a[i]].add(i, i)

for i in range(q):
    qry = list(input().split())
    if qry[0] == "1":
        _, k, x = qry
        k = int(k) - 1
        x = ordalp(x) # 0 ~ 25
        t[k] = x
        for i in range(max(k, 2), min(k+3, n)):
            c[a[i]].add(i, -1)
            s[a[i]].add(i, -i)
            a[i] = 0
            for j in range(-2, 1):
                a[i] *= 26
                a[i] += t[i+j]
            c[a[i]].add(i, 1)
            s[a[i]].add(i, i)
    elif qry[0] == "2":
        _, l, r, bb = qry
        l = int(l) - 1
        r = int(r) 
        if r - l < 3:
            print(0)
            continue
        b = 0
        for x in bb:
            b *= 26
            b += ordalp(x)
        rc = c[b].sum(l+2, r)
        rs = s[b].sum(l+2, r)
        # print(b, c[b], s[b])
        print(rs - rc * (l + 1))