Exponent calculator not functioning properly....

[working_with_c]

Here is the source I wrote.

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>




   
int main()
{
 int x;
 int y; 
 int total;
 int i; 
 


 
 
 i=0;
 total=1;
 
 
 printf("Enter a base limit for x : \n");
 scanf("%d",&x);
 
 printf("Enter an exponent limit for y: \n");
 scanf("%d",&y);
 
 while( i < y)
 {
  
  total = total * x ;
    
  i++;
        }
        
        printf("The total of %d raised to %d = %d", x,y,total);
getch();
getch();
return 0;
}

this calculator works for a majority of the math except :

100 ^ 100 = 0 in some cases

in another case the calculator is just plain wrong. EX:

19^9 = 322687697779

my calculator says:

19^9 = 565 150 579

Any advice on why this is happening so i can figure out how to fix it would be much appreciated.

Thank you for your time.

[Subsonics]

You are experiencing integer overflows. Import limits.h and print the value for the INT_MAX constant. 100 multiplied by itself 100 times is going to be a huge number for example.

Edit: to add some more to this. Most likely an int is 32 bits on your system which means the highest value you can ever store in it is going to be 2^32 -1. Since you are using a signed integer half of it's range is used for negative numbers, so in your case: 2^31 -1. When you go above the capacity you get a domino brick effect on the bits and you start over at 0.

[CommonTater]

@subsonics ... Given the inclusion of conio.h I'm betting it's Turbo C which might even be 16 bits... meaning his integer range is -32768 -> 32767. Not entirely condusive to storing 1.0e+200

[working_with_c]

Please be patient with me I'm new to this.
I understand implementing a missing definition limits.h

But I'm not sure how to implement INT_MAX in my code.

I looked around the site some and all i found was this:
how to handle integer overflow in C

This is probably what I need I just cant make any sense of it in relation to my code.

As far as the conio.h (that was just me fumbling threw the dark adding unnecessary information)


Thanks again all your help has been very useful.

[Subsonics]

You are not supposed to implement INT_MAX it's defined in limits.h and it will tell you how large an integer is on your system (or the largest value you can store in an integer actually). But there is an easier way: (sizeof(int) * 8) but I told you mostly as a way to understand the limits of what you can do, using your current approach.

For example (100 ^ 100): for a reference 10 ^ 100 is 1 googol, or (as I have heard) approximately the amount of molecules in the known universe, in other words, don't sweat it if you can not represent it in an integer.

The easiest way to solve this is probably to just assume 1 googol, then do: 10 ^ 2 = 100 googol.


Edit: Actually, I did some searching and it appears that: The amount of elementary particles in the known universe have been approximated to 10^80 i.e 100 trillion times fewer than 1 googol.

[AndrewHunter]

Please be patient with me I'm new to this.
I understand implementing a missing definition limits.h

But I'm not sure how to implement INT_MAX in my code.

Here is limits.h. You are going to need to change your variable type if you want to handle big numbers past INT_MAX. Something like a long or long long.

[GReaper]

More like double or long double. ( If that dinosaur supports them, that is... )