pointer arithmetic help

i don't know anything about pointers. i wrote this code couple of weeks ago.

Code:

#include<stdio.h>
#include<conio.h>
void main()
{
                int x[100],n,i;
                float mean(int,int[]);
                float median(int,int[]);

                scanf("%d",&n);
                for(i=0;i<n;i++)
                    scanf("%d",&x[i]);
                printf("mean=%f\n",mean(n,x));
                printf("median=%f\n",median(n,x));

}
 
float mean(int m,int a[])
{
	int sum=0,i;
	for(i= 0;i<m;i++)
	sum+=a[i];
	return((float)sum/m)	;
}
 
float median(int n,int x[])
{
	int i,j, temp;
	for(i=0;i<n-1;i++)
	for(j=i+1;j<n;j++)
	{
	      if(x[j]<x[i])
	    {
	        temp=x[i];
	        x[i]=x[j];
	        x[j]=temp;
	      }
	     if(n%2==0)
	    {
	         return((x[n/2]+x[n/2-1])/2.0); //i was told to change this line
	    }
	    else
	    return x[n/2]; //changed to return *(x+ (n/2));
	}
	
}

in the mean and median functions, i have to replace the array indexing with pointers.
i have no clue how this is to be done. any help will be appreciated.

Anywhere you had: foo[x]
Put: *(foo + x)

foo + x = an address
*(foo + x) = a value


Quzah.

Originally Posted by ihavesixtoes

i don't know anything about pointers. i wrote this code couple of weeks ago.

Code:

#include<stdio.h>
#include<conio.h>
void main()
{
                int x[100],n,i;
                float mean(int,int[]);
                float median(int,int[]);

                scanf("%d",&n);
                for(i=0;i<n;i++)
                    scanf("%d",&x[i]);
                printf("mean=%f\n",mean(n,x));
                printf("median=%f\n",median(n,x));

}
 
float mean(int m,int a[])
{
	int sum=0,i;
	for(i= 0;i<m;i++)
	sum+=a[i];
	return((float)sum/m)	;
}
 
float median(int n,int x[])
{
	int i,j, temp;
	for(i=0;i<n-1;i++)
	for(j=i+1;j<n;j++)
	{
	      if(x[j]<x[i])
	    {
	        temp=x[i];
	        x[i]=x[j];
	        x[j]=temp;
	      }
	     if(n%2==0)
	    {
	         return((x[n/2]+x[n/2-1])/2.0); //i was told to change this line
	    }
	    else
	    return x[n/2]; //changed to return *(x+ (n/2));
	}
	
}

in the mean and median functions, i have to replace the array indexing with pointers.
i have no clue how this is to be done. any help will be appreciated.

replace x[i] with *(x+i) and x[j] with *(x+j)

Originally Posted by nimitzhunter

replace x[i] with *(x+i) and x[j] with *(x+j)

do i also have to change

Code:

float median(int n,int x[])
 
to 

float median( int n, const int *)

?

please ignore the above.


i did exactly what you guys told me to do and it works. thank you vry vry much.

now i am off to learn pointers.