LeetCode-in-Go
135. Candy
Hard
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.length1 <= n <= 2 * 1040 <= ratings[i] <= 2 * 104
Solution
func candy(ratings []int) int {
candies := make([]int, len(ratings))
for i := range candies {
candies[i] = 1
}
for i := 0; i < len(ratings)-1; i++ {
if ratings[i+1] > ratings[i] {
candies[i+1] = candies[i] + 1
}
}
for i := len(ratings) - 1; i > 0; i-- {
if ratings[i-1] > ratings[i] && candies[i-1] < candies[i]+1 {
candies[i-1] = candies[i] + 1
}
}
total := 0
for _, candy := range candies {
total += candy
}
return total
}