Thread: Perfect Number program

In the Perfect Number Program, when I run the program I enter a number such for example 6 which is a perfect number after I put in the number it says its not a perfect number if I entered a different perfect number like 28, 496, 8128 it still says its not a perfect number. Is there something in my code that prevents from showing the perfect numbers after entering the number?

Code:

#include<stdio.h>
#include<math.h>

int main()
{

     int perfect(int c);
     int a,b,c,i;

     printf("Enter a Number: " );
     scanf("%d",&a);c=0;

     if(c==a) {
     printf("\nA perfect number\n");
}

     else
     printf("\nNot a perfect Number\n");


     return  0;
}

int perfect(int c)
{

       int a,b,i;

      for(i=1;i<a;i++)
      {


     b=a%i;
     if(b==0)
        {

        c=c+i;

       if(c==a) {

       printf("\nA perfect number\n");
       }
       else
            printf("\nNot a perfect Number\n");
       }
       return 0;
}
}

Some problems:

1) You never call the perfect function. All you have is a prototype of it, and the function, but execution is never going there.

2) You assign c the value of 0, then if(c==a) it's a perfect number?

Not the way to do it.

6, 28, 496, and 8128 are not "perfect numbers" because you assigned c to zero. The perfect function is dead code because you declared a prototype but never called it.

I see the red in int perfect() a few quotes ago that a was never initialized which I
don't understand what it means by not being initialized by int a; which
is declared in int perfect(), can you show me a example that would intialize
the variable a that is probably why the program isn't returning the information
for the perfect numbers?

Originally Posted by tiger6425

I see the red in int perfect() a few quotes ago that a was never initialized which I
don't understand what it means by not being initialized by int a; which
is declared in int perfect(), can you show me a example that would intialize
the variable a that is probably why the program isn't returning the information
for the perfect numbers?

There are more problems than just an uninitialized variable...
But anyway, to initialize a variable you give it a value when you create it.

int A = 11;

Never assume that creation results in 0.