EIU Programming Practices and Exams

Nam is still young but has managed to save a large amount of money. He wants to determine whether that amount is sufficient for financial freedom. The calculation is based on the following criteria: Nam invests the entire amount he has into a safe investment channel with an annual interest rate of r%. At the end of this year, Nam will withdraw an amount C to cover his expenses for one year. In the following years, Nam will withdraw an increasing amount based on the inflation rate of f% per year (f < r). Nam wants to ensure that he can continue withdrawing money like this indefinitely. Calculate the minimum amount of money Nam needs to have.

Note: The unit of measurement is in millions. Being able to withdraw money at least 10,000 years is considered indefinite.

Input

The only line contains 2 real numbers r and f, and an integer C (0 < f < r ≤ 20, 0 < C ≤ 1000). 

Output

Calculate the minimum amount of money Nam needs to have (rounded to the nearest integer).

Sample