Length of a valley

You are given an integer array $A$ consisting of $N$ elements. For each element, you are required to find the length of the valley that is defined as:

Let $i$ be the current index and $l$ and $r$ be the leftmost and rightmost index satisfying this property $a[l]>a[l+1].....>a[i-1]>a[i]<a[i+1]<...a[r-1]<a[r]$, then $(r-l+1)$ is the length of the valley. Also, assume that if $A$ is $[7,2,1,5,7,9]$, then the answer is $[1,2,6,3,2,1]$.

Example:

Input: n=6, arr[] = { 7, 2, 1, 5, 7, 9 }
Output: 1 2 6 3 2 1 

Approach

Java

public class LengthOFValley {
    public static void main(String[] args) {
        final int N = (int) 5e5 + 2;
        int a[] = new int[N];
        int l[] = new int[N], r[] = new int[N];
        a[0] = Integer.MIN_VALUE;
        int n = 6;
        int arr[] = { 7, 2, 1, 5, 7, 9 };
        for (int i = 1; i <= n; ++i) {
            a[i] = arr[i - 1];
        }
        a[n + 1] = Integer.MIN_VALUE;
        for (int i = 1, j = n; i <= n; ++i, --j) {
            if (a[i - 1] > a[i])
                l[i] = l[i - 1];
            else
                l[i] = i;
            if (a[j] < a[j + 1])
                r[j] = r[j + 1];
            else
                r[j] = j;
        }
        for (int i = 1; i <= n; ++i) {
            System.out.print((r[i] - l[i] + 1) + " ");
        }
    }

}