n=int(input())

B=224
k=26

def op(x,y):
  z=[0]*(k+k+1)
  for i in range(k+k+1):
    z[i]=x[i]+y[i]
  c=0
  for i in range(k):
    c+=x[i]*(x[i]-1)//2
  for i in range(k):
      z[-1]+=(c-x[i]*(x[i]-1)//2)*y[i]
  for i in range(k):
    z[-1]+=x[i]*y[k+i]
  c=0
  for i in range(k):
    c+=y[i]
  for i in range(k):
    z[k+i]+=x[i]*(c-y[i])
  return z

q1=[[0]*(k+k+1) for i in range(B*B)]
q2=[[0]*(k+k+1) for i in range(B)]

s=input()
for i in range(n):
  q1[i][ord(s[i])-ord("A")]=1

for i in range(B):
  q2[i]=[0]*(k+k+1)
  for j in range(B):
    q2[i]=op(q2[i],q1[i*B+j])

Q=int(input())
for _ in range(Q):
  t,p1,p2=input().split()
  t=int(t)
  if t==1:
    x=int(p1)-1
    c=p2
    q1[x]=[0]*(k+k+1)
    q1[x][ord(c)-ord("A")]=1
    y=x//B
    q2[y]=[0]*(k+k+1)
    for i in range(B):
      q2[y]=op(q2[y],q1[y*B+i])
  if t==2:
    l=int(p1)-1
    r=int(p2)-1
    yl=l//B
    yr=r//B
    q=[0]*(k+k+1)
    if yl==yr:
      for i in range(l,r+1):
        q=op(q,q1[i])
    else:
      for i in range(l,yl*B+B):
        q=op(q,q1[i])
      for i in range(yl+1,yr):
        q=op(q,q2[i])
      for i in range(yr*B,r+1):
        q=op(q,q1[i])
    print(q[-1])