Question

C语言问题，帮我看看我的代码哪里错了 北大ACM1003- Hangover

题目：
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)

我的C程序如下：
#include<stdio.h>
main()
{
int cards,i;
double longth,sum=0;
scanf("%lf",&longth);
while(cards!=0.00 && cards>=0.01 && cards<= 5.20){
cards=0,sum=0;
printf("longth=%lf\t",longth);
for(i = 2; sum <longth; i++) {
sum += 1.00/i;
cards++;}
printf("%d card(s)\n", cards);
scanf("%lf",&longth);}
return 0;
}

Answer 1

一点小错误：
while(cards!=0.00 && cards>=0.01 && cards<= 5.20)
里面的card全改成longth就可以了

Answer 2

引用l521088816的回答：
一点小错误：
while(cards!=0.00 && cards>=0.01 && cards<= 5.20)
里面的card全改成longth就可以了

他是错在#include<math.h>
没有加上去，因为他用到了数学符号！=这类的