Python 代码：
from typing import List
class Solution:
def maxEnvelopes(self, envelopes: List[List[int]]) -> int:
size = len(envelopes)
# 特判
if size < 2:
return size
# 对第一列排序，按照宽度排序
# 【特别注意】当宽度相等的时候，按照高度降序排序
# 以避免 [[11, 3], [12, 4], [12, 5], [12, 6], [14, 6]] 这种情况发生
# 正确排序 [[11, 3], [12, 6], [12, 5], [12, 4], [14, 6]]
envelopes.sort(key=lambda x: (x[0], -x[1]))
# print(envelopes)
tail = [envelopes[0][1]]
for i in range(1, size):
target = envelopes[i][1]
if target > tail[-1]:
tail.append(target)
continue
left = 0
right = len(tail) - 1
while left < right:
mid = (left + right) >> 1
if tail[mid] < target:
left = mid + 1
else:
right = mid
tail[left] = target
# print(tail)
return len(tail)
if __name__ == '__main__':
envelopes = [[4, 5], [4, 6], [6, 7], [2, 3], [1, 1]]
envelopes = [[30, 50], [12, 2], [3, 4], [12, 15]]
envelopes = [[1, 3], [3, 5], [6, 7], [6, 8], [8, 4], [9, 5]]
solution = Solution()
res = solution.maxEnvelopes(envelopes)
print(res)
