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:

• Time: O(n)
• Space: O(n)

public int candy(int[] rates)
    int[] candy = new int[rates.length];
    Arrays.fill(candy, 1);
    for (int i = 1; i < rates.length; i++) {
        if (rates[i - 1] < rates[i]) {
            candy[i] = candy[i - 1] + 1;
        }
    }
    for (int i = rates.length - 2; i >= 0; i--) {
        if (rates[i] > rates[i + 1] && candy[i] <= candy[i + 1]) {
            candy[i] = candy[i + 1] + 1;
        }
    }
    int ret = 0;
    for (int i = 0; i < candy.length; i++) {
        ret += candy[i];
    }
    return ret;
}