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uaecasher
Jun 16, 2009, 01:24 AM
Hello,

i have written this code:

#include <stdio.h>
int main (void)
{

int a = 15;
int b = 35;

printf("a / b * b = %i\n", a / b * b);

}

the result i get is zero, but it should be 15, why I'm getting a 0

thanks

Wes
Jun 16, 2009, 01:38 AM
You need to think about the order this is being evaluated, see: http://www.difranco.net/cop2220/op-prec.htm

a / b * b becomes (a / b) * b

where:
a = 15;
b = 35;

(15/35)*35
0*35

Remember these are integers so 15/35 will be 0. If you want to get the fractional part you'll need to use floats or doubles.

EMT
Jun 16, 2009, 01:57 AM
Use parenthesis in your expressions to make it safe.:

Sander
Jun 16, 2009, 02:11 AM
Use parenthesis in your expressions to make it safe.:

That wouldn't help in this case - it's the integer division that's the problem here.

gnasher729
Jun 16, 2009, 05:51 AM
Hello,

i have written this code:

#include <stdio.h>
int main (void)
{

int a = 15;
int b = 35;

printf("a / b * b = %i\n", a / b * b);

}

the result i get is zero, but it should be 15, why I'm getting a 0

thanks

It should be zero. Buy a C book for beginners.