ProductOfArrayExceptSelf.java

class ProductOfArrayExceptSelf {
    public int[] productExceptSelf(int[] nums) {
        if (nums.length < 2) {
            return nums;
        }
        int[] products = new int[nums.length];
        int factor = 1;
        for (int i = nums.length - 1; i >= 0; i--) {
            products[i] = factor * nums[i];
            factor = products[i];
        }
        factor = 1;
        for (int i = 0; i < nums.length - 1; i++) {
            products[i] = factor * products[i + 1];
            factor *= nums[i];
        }
        products[products.length - 1] = factor;
        return products;
    }
}