Codeforces #262 (Div. 2) A. Vasya and Socks（水题）

A. Vasya and Socks

time limit per test
1 second

memory limit per test
256 megabytes

input
standard input

output
standard output

Vasya has n pairs of socks. In the morning of each day Vasya has to put on a pair of socks before he goes to school. When he comes home in the evening, Vasya
takes off the used socks and throws them away. Every m-th day (at days with numbers m, 2m, 3m, ...)
mom buys a pair of socks to Vasya. She does it late in the evening, so that Vasya cannot put on a new pair of socks before the next day. How many consecutive days pass until Vasya runs out of socks?

Input

The single line contains two integers n and m (1 ≤ n ≤ 100; 2 ≤ m ≤ 100),
separated by a space.

Output

Print a single integer — the answer to the problem.

Sample test(s)

input

2 2

output

3

input

9 3

output

13

Note

In the first sample Vasya spends the first two days wearing the socks that he had initially. Then on day three he puts on the socks that were bought on day two.

In the second sample Vasya spends the first nine days wearing the socks that he had initially. Then he spends three days wearing the socks that were bought on the third, sixth and ninth days. Than he spends another day wearing the socks that were bought on
the twelfth day.

一道大水题，因为太着急了，所以刚写的时候细节没有考虑清楚

对于7 2这组数据

正确的结果应该是：13ans += 7/2×2 == 6

tmp = 7/2+7%2 = 4

ans += 4/2×2 == 10

tmp = 4/2+4%2 = 2

ans += 2/2×2 == 12

tmp = 2/2+2%2 = 1

ans += 1 == 13保存每次计算剩余的数量tmp是关键

代码如下：

#include <bits/stdc++.h>
using namespace std;

int main(void) {
int n, m, tmp, ans, cnt;
cin >> n >> m;
if(n < m) {
cout << n << endl;
return 0;
}
ans = n/m*m;
tmp = n;
while(tmp >= m) {
tmp = tmp/m+tmp%m;
ans += tmp/m*m;
}
if(tmp != n)
ans += tmp;
cout << ans << endl;

return 0;
}