Problem p03504 (python)

Fixed submission:
#!/usr/bin/env python3
#ABC80 D

import sys
import math
import bisect
sys.setrecursionlimit(1000000000)
from heapq import heappush, heappop,heappushpop
from collections import defaultdict
from itertools import accumulate
from collections import Counter
from collections import deque
from operator import itemgetter
from itertools import permutations
mod = 10**9 + 7
inf = float('inf')
def I(): return int(sys.stdin.readline())
def LI(): return list(map(int,sys.stdin.readline().split()))


n,C = LI()
stc = [LI() for _ in range(n)]
L = []
for i in range(C):
    lst = []
    for j in range(n):
        s,t,c = stc[j]
        if i+1 == c:
            lst.append([s,t])
    lst.sort(key = itemgetter(0))
    lst2 = []
    j = 0
    while j < len(lst):
        if j < len(lst)-1:
            if lst[j][1] == lst[j+1][0]:
                lst2.append((lst[j][0],lst[j+1][1]))
                j += 2
                continue

        lst2.append(tuple(lst[j]))
        j += 1
    L.append(lst2)
x = [[0]*100002 for _ in range(C)]
for i in range(C):
    for j,k in L[i]:
        x[i][j] += 1
        x[i][k+1] -= 1
    x[i] = list(accumulate(x[i]))
ans = 0
for i in range(1,10**5+1):
    s = 0
    for j in range(C):
        if x[j][i] == 1:
            s += 1
    ans = max(ans,s)
print(ans)

Buggy submission (verdict: Runtime Error):
#!/usr/bin/env python3
#ABC80 D

import sys
import math
import bisect
sys.setrecursionlimit(1000000000)
from heapq import heappush, heappop,heappushpop
from collections import defaultdict
from itertools import accumulate
from collections import Counter
from collections import deque
from operator import itemgetter
from itertools import permutations
mod = 10**9 + 7
inf = float('inf')
def I(): return int(sys.stdin.readline())
def LI(): return list(map(int,sys.stdin.readline().split()))

n,C = LI()
cha = [[] for _ in range(C)]
ans = 0
lst = [0]*(10**5+1)
for _ in range(n):
    s,t,c = LI()
    cha[c-1].append([s,t])
for i in range(C):
    if len(cha[i]) == 0:
        continue
    cha[i].sort(key = itemgetter(0))
    s,t = cha[i][0]
    tmp = []
    for j in range(1,len(cha[i])):
        if t == cha[i][j][0]:
            t = cha[i][j][1]
        else:
            tmp.append([s,t])
            s,t = cha[i][j]
    tmp.append([s,t])
    for i,j in tmp:
        lst[i] += 1
        lst[j+1] -= 1
lst = list(accumulate(lst))
print(max(lst))

Buggy submission (verdict: Runtime Error):
#!/usr/bin/env python3
#ABC80 D

import sys
import math
import bisect
sys.setrecursionlimit(1000000000)
from heapq import heappush, heappop,heappushpop
from collections import defaultdict
from itertools import accumulate
from collections import Counter
from collections import deque
from operator import itemgetter
from itertools import permutations
mod = 10**9 + 7
inf = float('inf')
def I(): return int(sys.stdin.readline())
def LI(): return list(map(int,sys.stdin.readline().split()))


n,C = LI()
stc = [LI() for _ in range(n)]
L = []
for i in range(C):
    lst = []
    for j in range(n):
        s,t,c = stc[j]
        if i+1 == c:
            lst.append([s,t])
    lst.sort(key = itemgetter(0))
    lst2 = []
    j = 0
    while j < len(lst):
        if j < len(lst)-1:
            if lst[j][1] == lst[j+1][0]:
                lst2.append((lst[j][0],lst[j+1][1]))
                j += 2
                continue

        lst2.append(tuple(lst[j]))
        j += 1
    L.append(lst2)
x = [[0]*100001 for _ in range(C)]
for i in range(C):
    for j,k in L[i]:
        x[i][j] += 1
        x[i][k+1] -= 1
    x[i] = list(accumulate(x[i]))
ans = 0
for i in range(1,10**5+1):
    s = 0
    for j in range(C):
        if x[j][i] == 1:
            s += 1
    ans = max(ans,s)
print(ans)