Simple cube and square sum function won't run (C)

Question

Learning C, trying to code a program that outputs the sum of the cube and square of an inputted number.

#include <stdio.h>

main()
{
int a;
scanf("%d",a);
printf("%d",cube(a)+sqr(a));
}

cube(int x)
{
return(x*x*x);
}

sqr(int arg)
{
return(arg*arg);
}

When I run the program it outputs some seemingly random string of numbers after I input a number. Any way to fix it without changing the usage of returns to assign variables?

always compile you code as: `gcc -Wall -pedantic code.c -c exe` — Grijesh Chauhan, Jul 23 '13 at 10:05

score 5 · Accepted Answer · edited Jul 23 '13 at 10:04

5

scanf needs a pointer:

scanf("%d",&a);

instead of

scanf("%d",a);

edited Jul 23 '13 at 10:04

David Ranieri

39,972
7
52
94

answered Jul 23 '13 at 10:02

hivert

10,579
3
31
56

Thanks lol was such a simple mistake – freshc Jul 23 '13 at 10:03
2

Your compiler should have warned you about this one. Are you compiling with ``-Wall`` (gcc/linux) ? – hivert Jul 23 '13 at 10:05
don't know what that means.. I'm using codeblocks and it ran the program but crashed after input – freshc Jul 23 '13 at 10:09
2

In "project -> Build options -> Compiler settings -> Compiler flags" you should check "enable all compiler warnings" and pay attention to those warnings. – hivert Jul 23 '13 at 10:13

score 4 · Answer 2 · answered Jul 23 '13 at 10:02

4

int a;
scanf("%d",a);

          ^

must be &a. d conversion specifier for scanf expects a pointer to int argument.

answered Jul 23 '13 at 10:02

ouah

142,963
15
272
331

score 0 · Answer 3 · answered Jul 23 '13 at 10:00

0

You need to define a return type to your functions !

#include <stdio.h>

int main()
{
  int a;
  scanf("%d",a);
  printf("%d",cube(a)+sqr(a));
  return 0;
}

int cube(int x)
{
  return(x*x*x);
}

int sqr(int arg)
{
  return(arg*arg);
}

answered Jul 23 '13 at 10:00

dotixx

1,490
12
23

2

Actually it looks like he's using an old compiler which supports implicit int return types. – Paul R Jul 23 '13 at 10:01
Tried your code and it has the same problem. I believe in C, int is implied if the return type isn't specified. – freshc Jul 23 '13 at 10:03
@PaulR I didn't know about this, my bad sry x) – dotixx Jul 23 '13 at 10:03
No problem - this kind of C usage is about 20 - 30 years out of date ! – Paul R Jul 23 '13 at 10:04
NP the solution was posted anyways thanks for trying! – freshc Jul 23 '13 at 10:04

score 0 · Answer 4 · answered Jul 23 '13 at 10:09

0

You have not given address of "a" in scanf function.

Please use:

scanf("%d", &a);

answered Jul 23 '13 at 10:09

stev

182
1
11

`&a` is not the address of `a`. The address will be hexadecimal. `&a` just gives the address of `a` to `scanf`. – Box Box Box Box Feb 18 '16 at 09:12

Simple cube and square sum function won't run (C)

4 Answers4