There are N children standing in a line. Each child is assigned a rating value.
You are giving candies to these children subjected to the following requirements:
Each child must have at least one candy.Children with a higher rating get more candies than their neighbors.What is the minimum candies you must give?
class Solution {
public: int candy(vector<int> &ratings) { /* 遍历两边，首先每个人得一块糖，第一遍从左到右，若当前点比前一个点高就比前者多一块。 这样保证了在一个方向上满足了要求。第二遍从右往左，若左右两点，左侧高于右侧，但 左侧的糖果数不多于右侧，则左侧糖果数等于右侧糖果数+1，这就保证了另一个方向上满足要求 */ int n=ratings.size(); vector<int> child(n); for(int i=0;i<n;i++) child[i]=1; int i=0; for(i=1;i<n;i++) { if(ratings[i]>ratings[i-1]) child[i]=child[i-1]+1; } for(i=n-2;i>=0;i--) { if(ratings[i]>ratings[i+1]&&child[i]<=child[i+1]) child[i]=child[i+1]+1; } return accumulate(child.begin(),child.end(),0); } };