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 Ruby (2.3.3) (judge verdict: Runtime Error)

line = STDIN.gets
produceTime = line.slice(0, 1).to_i
produceNum = line.slice(2, 1).to_i
finishTime = line.slice(4, 1).to_i + 0.5
# p produceTime
# p produceNum
# p finishTime
biscuitNum = 0
nextTime = produceTime
N = 20
N.times do |i|
    # p "i:" + i.to_s
    if i == nextTime
        biscuitNum += produceNum
        # p "biscuitNum: " + biscuitNum.to_s
        nextTime += produceTime
        # p "nextTime: " + nextTime.to_s
    end
    if i >= finishTime
        puts biscuitNum
        return
    end
end