边工作边刷题：70天一遍leetcode: day 12-1

Candy

要点：又是左右扫描的题，从左向右简单，就是初始为1，和左边的rating比较。从右向左就直接用一个right变量，这个值每次更新都是最终i的糖果数同时作为前一个最终值的依据：初始为最后一个left的值，之后就是根据rating更新取大。

class Solution(object):
    def candy(self, ratings):
        """
        :type ratings: List[int]
        :rtype: int
        """
        n = len(ratings)
        left = [1]*n
        for i in range(1, n):
            if ratings[i]>ratings[i-1]:
                left[i]=left[i-1]+1
        
        right = left[n-1]
        minCandy = right
        for i in range(n-2, -1, -1):
            if ratings[i]>ratings[i+1]:
                right = max(right+1, left[i])
            else:
                right=left[i]
        
            minCandy +=right
        
        return minCandy