300. 最长上升子序列
方法一
class Solution:
def lengthOfLIS(self, nums):
"""
:type nums: List[int]
:rtype: int
nums = [10, 9, 2, 5, 3 ,7, 101, 18]
"""
if not nums: return 0
dp = [1] * len(nums)
res = 1
for i in range(len(nums)):
for j in range(i):
if nums[i] > nums[j]:
dp[i] = max(dp[i], dp[j] + 1)
res = max(res, dp[i])
return res
方法二
class Solution:
def lengthOfLIS(self, nums):
"""
:type nums: List[int]
:rtype: int
nums = [10, 9, 2, 5, 3 ,7, 101, 18]
"""
if not nums:
return 0
lis = [nums[0]]
for i in range(1, len(nums)):
if nums[i] > lis[-1]:
lis.append(nums[i])
else:
for j in range(len(lis)):
if lis[j] >= nums[i]:
lis[j] = nums[i]
break
return len(lis)
方法三
class Solution:
def lengthOfLIS(self, nums):
"""
:type nums: List[int]
:rtype: int
nums = [10, 9, 2, 5, 3 ,7, 101, 18]
"""
if not nums: return 0
res = [nums[0]]
for i in range(1, len(nums)):
if nums[i] > res[-1]:
res.append(nums[i])
else:
l, r, mid = 0, len(res)-1, 0
while l <= r:
mid = (l + r) // 2
if nums[i] > res[mid]:
l = mid + 1
else:
r = mid - 1
res[l] = nums[i]
return len(res)