codeforces -- goodbye2013 ---A. New Year Candles

A. New Year Candles

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

Vasily the Programmer loves romance, so this year he decided to illuminate his room with candles.

Vasily has a candles.When Vasily lights up a new candle, it first burns for an hour and then it goes out. Vasily is smart, so he can makeb went out candles into a new candle. As a result, this new candle can be used like any other new candle.

Now Vasily wonders: for how many hours can his candles light up the room if he acts optimally well? Help him find this number.

Input

The single line contains two integers, a andb (1 ≤ a ≤ 1000; 2 ≤ b ≤ 1000).

Output

Print a single integer — the number of hours Vasily can light up the room for.

Sample test(s)

Input

4 2

Output

7

Input

6 3

Output

8

Note

Consider the first sample. For the first four hours Vasily lights up new candles, then he uses four burned out candles to make two new ones and lights them up. When these candles go out (stop burning), Vasily can make another candle. Overall, Vasily can light up the room for 7 hours.

这一个题主要是b个燃烧后的蜡烛可以换一个新蜡烛， 这样一直换到燃烧后的蜡烛小于b ， 用while循环 直到 燃烧后的蜡烛小于b结束  统计时间

#include <stdio.h>
int main()
{
    int a, b , c = 0 , h = 0 ;
    scanf("%d %d",&a, &b);
    while(1)
    {
        h += a ;
        c += a ;
        a = c / b ;
        if(c < b) break;
        c %= b ;
    }
    printf("%d\n", h);
    return 0;
}