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.
class Solution:
def candy(self, ratings: List[int]) -> int:
candy = [1] * len(ratings)
for i in range(len(candy)-1):
if ratings[i+1] > ratings[i]:
candy[i+1] = candy[i] + 1
for i in range(len(candy)-1, 0, -1):
if ratings[i-1] > ratings[i]:
candy[i-1] = max(candy[i]+1, candy[i-1])
return sum(candy)