POJ1003超水练手题 Hangover

链接：http://poj.org/problem?id=1003

Time Limit: 1000MS		Memory Limit: 10000K
Total Submissions: 99711		Accepted: 48362

Description

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.

Input

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.

Output

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.

Sample Input

1.00
3.71
0.04
5.19
0.00

Sample Output

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

Source

Mid-Central USA 2001

#include<cstdio>
int main(void){

    while(1){
        float shuru;
        scanf("%f",&shuru);
        if(shuru<0.001)
            break;
        float i=2;
        float chang=0;
        while(chang<shuru){
            chang=1/i+chang;
            i++;
        }
        int d=int(i);
        printf("%d card(s)\n",d-2);
    }
    return 0;
}