8.6笔记

回顾：

300. 最长上升子序列

第一种方法（dp）

class Solution(object):
    def lengthOfLIS(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        if not nums:
            return 0
        dp = [1]*len(nums)
        for i in range(1,len(nums)):
            for j in range(i):
                if nums[i] > nums[j]:
                    dp[i] = max(dp[i],dp[j]+1)
        return max(dp)

第二种方法（二分）

class Solution:
    def lengthOfLIS(self, nums: List[int]) -> int:
        c = [0]*len(nums)
        size = 0
        for num in nums:
            i,j = 0,size
            while i!=j:
                m = (i+j) // 2
                if c[m] < num:
                    i = m+1
                else:
                    j = m
            c[i] = num
            size = max(size,i+1)
        return size

518. 零钱兑换 II

class Solution(object):
    def change(self, amount, coins):
        """
        :type amount: int
        :type coins: List[int]
        :rtype: int
        """
        dp = [0]*(amount+1)
        dp[0]=1
        for coin in coins:
            for i in range(amount):
                if i+coin <=amount:
                    dp[i+coin]+=dp[i]
        return dp[-1]