积分赛（一）订正补题
原题
A - HangOver HDU - 1056
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.
Input
1.00
3.71
0.04
5.19
0.00
Output
3 card(s)
61 card(s)
1 card(s)
273 card(s)
代码
#include <iostream>
using namespace std;
int main()
{
double c,s=0,n=0;
int i=0,a[100000]={
};//这里数组至少要开1e5才能过
while(cin>>c)
{
if(c==0) break;
if(c>0)
{
for(n=0,s=0;s<c;n++)
{
s=s+1/(n+2);
}
a[i]=n;
i++;
}
}
for(int m=0;m<i;m++)
{
cout<<a[m]<<" "<<"card(s)"<<endl;
}
return 0;
}