hdoj 1045 Climbing Worm

Climbing Worm


Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 8979    Accepted Submission(s): 5849

Problem Description
An inch worm is at the bottom of a well n inches deep. It has enough energy to climb u inches every minute, but then has to rest a minute before climbing again. During the rest, it slips down d inches. The process of climbing and resting then repeats. How long before the worm climbs out of the well? We'll always count a portion of a minute as a whole minute and if the worm just reaches the top of the well at the end of its climbing, we'll assume the worm makes it out.
 
Input
There will be multiple problem instances. Each line will contain 3 positive integers n, u and d. These give the values mentioned in the paragraph above. Furthermore, you may assume d < u and n < 100. A value of n = 0 indicates end of output.
 
Output
Each input instance should generate a single integer on a line, indicating the number of minutes it takes for the worm to climb out of the well.
 
Sample Input
10 2 1
20 3 1
0 0 0
 
Sample Output
17
19
 
Source

East Central North America 2002

题目意思明确，这是一道模拟算法题，找到worm爬出well的时间，根据不同的时间点依次累加时间即可。

#include <iostream>    using namespace std;    int main()  {   int d, u, n;   int time,len;   while (cin >> n >> u >> d && (u + d + n)) {    len = time = 0;    while (len < n) {     time ++;     if (time%2 == 1) len += u;     else len -= d;    }    cout << time << endl;   }   return 0;  }