Problem:
Score : 100 points

Problem Statement

A biscuit making machine produces B biscuits at the following moments: A seconds, 2A seconds, 3A seconds and each subsequent multiple of A seconds after activation.

Find the total number of biscuits produced within T + 0.5 seconds after activation.

Constraints

All values in input are integers.

1 \leq A, B, T \leq 20

Input

Input is given from Standard Input in the following format:

A B T

Output

Print the total number of biscuits produced within T + 0.5 seconds after activation.

Sample Input 1

3 5 7

Sample Output 1

10

Five biscuits will be produced three seconds after activation.

Another five biscuits will be produced six seconds after activation.

Thus, a total of ten biscuits will be produced within 7.5 seconds after activation.

Sample Input 2

3 2 9

Sample Output 2

6

Sample Input 3

20 20 19

Sample Output 3

0

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

namespace kadai2
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] array = Console.ReadLine().Split(' ');
            int a = int.Parse(array[0]);
            int b = int.Parse(array[1]);
            int t = int.Parse(array[2]);
            int sum = 0;
            int i;

            if (a < 1 || a > 20 || b < 1 || b > 20 || t < 1 || t > 20)
                Console.WriteLine("エラー");

            else
            {
                for(i=a; i<t+0.5; i = i + a)
                {
                    sum = sum+b;
                }
                Console.WriteLine(sum);
            }
        }
    }
}