n = int(input())
m = []
SIZE = 30001
result = [0] * SIZE
for i in range(n):
    m.append(list(map(int,input().split())))
m.sort(key = lambda x: x[1])
for i in range(n):
    start = m[i][0]
    end = m[i][1]
    fail = 0
    for j in range(start):
        fail = max(fail,result[j])
    result[end] = fail + 1
maxn = 0
for i in range(SIZE):
    maxn = max(maxn, result[i])
print(maxn)

what`s wrong ?

Edited by author 25.11.2022 03:04

Edited by author 25.11.2022 03:04