Problem p02763 (python)

Fixed submission:
from bisect import bisect_left

n = int(input())
s = list(input())
q = int(input())
query = [input() for _ in range(q)]

p = [[] for _ in range(26)]

for i, x in enumerate(s):
    p[ord(x) - ord('a')].append(i)

for x in query:
    a, b, c = x.split()
    #print(c)
    if a == '1':
        b = int(b) - 1
        if s[b] == c:
            continue
        d = ord(s[b]) - ord('a')
        e = ord(c) - ord('a')
        temp = bisect_left(p[d], b)
        p[d].pop(temp)
        temp = bisect_left(p[e], b)
        p[e].insert(temp, b)
        s[b] = c
    else:
        b = int(b) - 1
        c = int(c) - 1
        #print(b, c)
        ans = 0
        for i in range(26):
            L = bisect_left(p[i], b)
            if L >= len(p[i]):
                continue
            if p[i][L] <= c:
                ans += 1
        print(ans)

Buggy submission (verdict: Runtime Error):
import bisect
N=input()
S=list(input())
alphabet=[[] for _ in range(26)]
for i,s in enumerate(S):
    alphabet[ord(s)-ord('a')].append(i)
Q=int(input())
for _ in range(Q):
    Type,A,B=input().split()
    if Type=="1":
        A=int(A)
        s=S[A-1]
        if s==B:
            continue
        o=ord(s)-ord("a")
        alphabet[o].pop(bisect.bisect_left(alphabet[o],A-1))
        index=bisect.bisect(alphabet[B-1],A-1)
        alphabet[B-1].insert(index,A-1)
        S[A-1]=B
    else:
        A=int(A)
        B=int(B)
        ans=0
        for i in range(26):
            indexL=bisect.bisect_left(alphabet[i],A-1)
            #indexR=bisect.bisect_right(alphabet[i],B-1)
            #ans+=(indexL!=indexR)
            if indexL==len(alphabet[i]):
                continue
            ans+=(alphabet[i][indexL]<=B-1)
        print(ans)

Buggy submission (verdict: Runtime Error):
import bisect
N=input()
S=list(input())
alphabet=[[] for _ in range(26)]
for i,s in enumerate(S):
    alphabet[ord(s)-ord('a')].append(i)
Q=int(input())
for _ in range(Q):
    Type,A,B=input().split()
    if Type=="1":
        A=int(A)
        s=S[A-1]
        if s==B:
            continue
        o=ord(s)-ord("a")
        alphabet[o].pop(bisect.bisect_left(alphabet[o],A-1))
        index=bisect.bisect(alphabet[o],A-1)
        #alphabet[o]=alphabet[o][:index]+[A-1]+alphabet[o][index:]
        #bisect.insort(alphabet[o],A-1)
        alphabet[B-1].insert(index,A-1)
        S[A-1]=B
    else:
        A=int(A)
        B=int(B)
        ans=0
        for i in range(26):
            indexL=bisect.bisect_left(alphabet[i],A-1)
            #indexR=bisect.bisect_right(alphabet[i],B-1)
            #ans+=(indexL!=indexR)
            if indexL==len(alphabet[i]):
                continue
            ans+=(alphabet[i][indexL]<=B-1)
        print(ans)

Buggy submission (verdict: Runtime Error):
import bisect
N=input()
S=list(input())
alphabet=[[] for _ in range(26)]
for i,s in enumerate(S):
    alphabet[ord(s)-ord('a')].append(i)
Q=int(input())
for _ in range(Q):
    Type,A,B=input().split()
    if Type=="1":
        A=int(A)
        s=S[A-1]
        o=ord(s)-ord("a")
        alphabet[o].pop(bisect.bisect_left(alphabet[o],A-1))
        index=bisect.bisect(alphabet[o],A-1)
        #alphabet[o]=alphabet[o][:index]+[A-1]+alphabet[o][index:]
        #bisect.insort(alphabet[o],A-1)
        alphabet[ord(B)-ord("a")].insert(index,A-1)
        S[A-1]=B
    else:
        A=int(A)
        B=int(B)
        ans=0
        for i in range(26):
            indexL=bisect.bisect_left(alphabet[i],A-1)
            #indexR=bisect.bisect_right(alphabet[i],B-1)
            #ans+=(indexL!=indexR)
            if indexL==len(alphabet[i]):
                continue
            ans+=(alphabet[i][indexL]<=B-1)
        print(ans)