There are n
children standing in a line. Each child is assigned a rating value given in the integer array ratings
.
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. Return the minimum number of candies you need to have to distribute the candies to the children.
Example 1:
Input: ratings = [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: ratings = [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.
Constraints:
n == ratings.length
1 <= n <= 2 * 10^{4}
0 <= ratings[i] <= 2 * 10^{4}

