C中的浮点异常(核心转储)

Question

在编写C程序并用fedora 32编译它时，当我试图从终端扫描用户输入时，我总是收到这个消息Floating point exception (core dumped)，我不知道我做错了什么。

我把一些printf函数放在中间，以知道它在哪里停止，我发现scanf ("%i", &number);函数不能正确读取或保存输入。

这是一些代码：

#include <stdio.h>
int main (void)
{
int number, constant, remain, remain1, mod, count, test;

number = 0;
mod = 1;
count = 0;
printf ("Enter a number to write: n");
scanf ("%i", &number);

printf ("-1");

constant = number;
test = number;
printf ("0");
if (number < 0)
{
number = number * -1;
printf ("-");
}
printf ("1");
while (test != 0)
{
test /= 10;
count++;
printf ("%i", count);
}
printf ("2");
for (int i = 1; i < count; i++)
{
mod = mod * 10; 
}
printf ("3");
while (number != 0)
{

remain = number % mod;
remain1 = constant - remain * mod;

switch (remain)
{
case 0:
printf ("Zero");
break;
case 1:
printf ("One");
break;
case 2:
printf ("Two");
break;
case 3:
printf ("Three");
break;
case 4:
printf ("Four");
break;
case 5:
printf ("Five");
break;
case 6:
printf ("Six");
break;
case 7:
printf ("Seven");
break;
case 8:
printf ("Eight");
break;
case 9:
printf ("Nine");
break;
}
remain = remain1;
mod /= 10;
}

printf ("n");

return 0;
}

Answer 1

按照我最初的猜测编辑-它是除以零

if(!mod ) // add this if 
{printf("Division by zero");exit(0);} //
remain = number % mod;

---

始终检查scanf的结果。Yuo在这里没有任何浮点运算，但可能在没有显示的代码中有被零除的部分。

#include <stdio.h>
int main (void)
{
int number, constant, remain, remain1, mod, count, test;

number = 0;
mod = 1;
count = 0;
printf ("Enter a number to write: n");
if(scanf ("%i", &number) != 1)
{
printf("scanf errorn");
}
else
{    
printf ("-1");

constant = number;
test = number;
printf ("0");
if (number < 0)
{
number = number * -1;
printf ("-");
}
printf ("1");
while (test != 0)
{
test /= 10;
count++;
printf ("%i", count);
}
printf ("2");
for (int i = 1; i < count; i++)
{
mod = mod * 10; 
}
}
}

在这里，这个功能变得很简单：

char *digits[] = {"Zero","One","Two","Three","Four","Five","Six","Seven","Eight","Nine"};
void printWord(int x)
{
int work = x;
long val = 1;
while(work)
{
val *= 10;
work /= 10;
}
val /= 10;
if(x < 0) printf("Minus");
if(!x) val = 10;
do
{
printf("%s", digits[abs(x / val)]);
x %= val;
val /= 10;
}while(x);
}
int main (void)
{
printWord(0);    
return 0;
}

https://godbolt.org/z/q4oWqT

Answer 2

此语句：

mod /= 10;

最终得到包含0的CCD_ 5。然后这个声明：

remain = number % mod;

导致除以0运算