The constant percentage method of computing depreciation of an asset is based on the assumption that the depreciation charge at the end of each year is a fixed percentage of the book value of the asset at the beginning of the year. This assumption leads to the following relationship: S = C (1 - d)^n where

C = original cost of asset,

D = depreciation rate per year,

n = number of years,

S = book value at the end of n years.

Write a program to compute the number of years of useful life of an asset given the original cost, depreciation rate, and book value at the end of its useful life (called scrap value). [Approach: Read the original cost (C), depreciation rate (D), book value at the end of useful life of an asset (S). Then, calculate the useful like of the asset (n)]