今天忙社博，之後補解釋~

class Solution {
public:
    int candy(vector<int>& ratings) {
        int n = ratings.size();
        int candy = n;
        int i = 1;
        while(i < n){
            if(ratings[i] == ratings[i - 1]){
                i++;
                continue;
            }

            int peak = 0;
            while(ratings[i] > ratings[i - 1]){
                peak++;
                candy += peak;
                i++;
                if(i == n){
                    return candy;
                }
            }

            int valley = 0;
            while(i < n && ratings[i] < ratings[i - 1]){
                valley++;
                candy += valley;
                i++;
            }
            candy -= min(peak, valley);
        }
        return candy;
    }
};