leetcode_238_2.java

public int[] productExceptSelf(int[] nums) {
    int n = nums.length;
    int[] left = new int[n], right = new int[n], arr = new int[n];
    left[0] = 1;
    right[n-1] = 1;
    for (int i=1; i<n; i++) {
        left[i] = left[i-1]*nums[i-1];
        right[n-i-1] = right[n-i]*nums[n-i];
    }
    for (int i=0; i<n; i++)
        arr[i] = left[i]*right[i];
    return arr;
}