杭电ACM 三 重力搭牌

How far can you make a stack of cards overhang a table? If you have one card, you can create a maximum overhang of half a card length. (We‘re assuming that the cards must be perpendicular to the table.) With two cards you can make the top card overhang the bottom one by half a card length, and the bottom one overhang the table by a third of a card length, for a total maximum overhang of 1/2 + 1/3 = 5/6 card lengths. In general you can make n cards overhang by 1/2 + 1/3 + 1/4 + ... + 1/(n + 1) card lengths, where the top card overhangs the second by 1/2, the second overhangs tha third by 1/3, the third overhangs the fourth by 1/4, etc., and the bottom card overhangs the table by 1/(n + 1). This is illustrated in the figure below.



The input consists of one or more test cases, followed by a line containing the number 0.00 that signals the end of the input. Each test case is a single line containing a positive floating-point number c whose value is at least 0.01 and at most 5.20; c will contain exactly three digits.

For each test case, output the minimum number of cards necessary to achieve an overhang of at least c card lengths. Use the exact output format shown in the examples.

1.00
3.71
0.04
5.19
0.00

3 card(s)
61 card(s)
1 card(s)
273 card(s)

/*
*Copyright (c)2014,烟台大学计算机与控制工程学院
*All rights reserved.
*文件名称：team.cpp
*作    者：冷基栋
*完成日期：2015年2月15日
*版 本 号：v1.0
*/
#include <iostream>
using namespace std;
int main()
{
    std::ios::sync_with_stdio(false);
    double m,n;
    int i;
    while (cin>>n)
    {
        m=0;
        i=0;
        if (n<0.01||n>5.20)
            break;
        while (m<n)
        {
            m+=1.00/(i+2);
            i++;
        }
        cout<<i<<" card(s)"<<endl;
    }
    return 0;
}