135. Candy
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?
Example 1:
Input: [1,0,2] Output: 5 Explanation: You can allocate to the first, second and third child with 2, 1, 2 candies respectively.
Example 2:
Input: [1,2,2] Output: 4 Explanation: You can allocate to the first, second and third child with 1, 2, 1 candies respectively. The third child gets 1 candy because it satisfies the above two conditions.
题意:给定一个数组,每个数组项代表一排小朋友的等级,比较相邻小朋友,等级高的比等级低的拿的糖果多。求给出总糖果数量?
代码如下:
/** * @param {number[]} ratings * @return {number} */ var candy = function(ratings) { // init let candies=new Array(ratings.length).fill(1); // from left to right for(let i=1;i<ratings.length;i++){ if(ratings[i]>ratings[i-1]){ candies[i]=candies[i-1]+1; } } // from right to left for(let i=ratings.length-2;i>=0;i--){ if(candies[i]<=candies[i+1] && ratings[i]>ratings[i+1]){ candies[i]=candies[i+1]+1; } } // get sum return candies.reduce(function(prev,curr){return prev+curr}); };