# Write a python function to find sum of products of all possible subarrays.
def sum_Of_Subarray_Prod(arr, n):
    ans = 0
    res = 0
    i = n - 1
    while i >= 0:
        incr = arr[i] * (1 + res)
        ans += incr
        res = incr
        i -= 1
    return ans
