what's this???

[questions]

Today when I build a program,the compiler tells me there is no
error,but when I run it ,it shows " 1.#INF00000",wh at's the
meaning??????Th e program is as follows:
#include<stdio. h>
int main()
{ int x,y;
int w=0;
long double z=0;

for(x=0;x<=10;x ++)

{if(x==0)

{w=1;}

else

{for(y=1;y<=x;y ++)

{w*=y;} }

z+=(float)1/w;}



printf("%.9Lf", z);


return 0;}

[Pawel Dziepak]

Re: what's this???

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questions wrote:

Today when I build a program,the compiler tells me there is no
error,but when I run it ,it shows " 1.#INF00000",wh at's the
meaning??????Th e program is as follows:
#include<stdio. h>
int main()
{ int x,y;
int w=0;
long double z=0;
>
for(x=0;x<=10;x ++)
>
{if(x==0)
>
{w=1;}
>
else
>
{for(y=1;y<=x;y ++)
>
{w*=y;} }
>
z+=(float)1/w;}
>
>
>
printf("%.9Lf", z);
>
>
return 0;}

It looks like "int" is too small to fit the value you assign to w. You
should check which type is sufficient (limits.h). According to C++
standard the largest integer type is unsigned long int and the largest
floating point type is long double. In fact, the second one was enough
to made this code working on my implementation.

I'd suggest you to format your code in an easier to read way.

Pawel Dziepak
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[Rolf Magnus]

Re: what's this???

questions wrote:

Today when I build a program,the compiler tells me there is no
error,but when I run it ,it shows " 1.#INF00000",wh at's the
meaning??????

One question mark is enough. More makes the question just look silly.
The meaning is probably that you are dividing by zero.
The maximum value that w would reach probably a lot bigger than int
can handle on your platform.

[maverik]

Re: what's this???

#include<stdio. h>

z+=(float)1/w;}

printf("%.9Lf", z);

Should you post to the c.l.c instead of c.l.c++

what's the meaning??????

Looks like w is overflowed. Use long types / float, double / ...

[want.to.be.professer]

Re: what's this???

On 11ÔÂ8ÈÕ, ÏÂÎç5ʱ37·Ö, questions <mengqidhu...@y ahoo.cnwrote:

Today when I build a program,the compiler tells me there is no
error,but when I run it ,it shows " 1.#INF00000",wh at's the
meaning??????Th e program is as follows:
#include<stdio. h>
int main()
{ int x,y;
int w=0;
long double z=0;
>
for(x=0;x<=10;x ++)
>
{if(x==0)
>
{w=1;}
>
else
>
{for(y=1;y<=x;y ++)
>
{w*=y;} }
>
z+=(float)1/w;}
>
printf("%.9Lf", z);
>
return 0;}

overflow!!!
You can see by this:

#include<stdio. h>
int main()
{
int x,y;
int w=0;
long double z=0;

for(x=0;x<=10;x ++)
{
if(x==0)
{
w=1;
}
else
{
for(y=1;y<=x;y+ +)
{
w*=y;
}
}
printf( " w : %d \n", w );
z+=(float)1/w;
printf("%.9Lf\n ",z);
}
printf("%.9Lf\n ",z);
return 0;
}