C PROGRAMMING QUESTION! This program works, (it is supposed to return a reversed

Question

C PROGRAMMING QUESTION! This program works, (it is supposed to return a reversed string) but my assignment is to have the string print in main() how can I edit the code to do this? Thank you!

#include <stdio.h>

#define STRINGLENGTH 100
void reverse(char*);
int main()
{
   char words[STRINGLENGTH];
   char *p;
   p = words;

   printf("I reverse strings! Enter a string: ");
   fgets(words, 100, stdin);

   printf("The reversed string is: ");

   reverse(p);

   return 0;

}

void reverse(char *p)
{
   char x;
   int end = strlen(p)-1;

   for (x = end; x >= 0; --x)
   {
       printf("%c", p[x]);
   }
}

Explanation / Answer

#include<stdio.h>
#include<string.h>

#define STRINGLENGTH 100

void reverse(char*);

int main()
{
char words[STRINGLENGTH];
printf(" I reverse strings! Enter a string: ");
fgets(words, 100, stdin);
   words[strlen(words)-1]=''; /*As fgets append a newline implicitlly at the end of string,
                                   I have just replaced it by null charecter '' */
   reverse(words);
   printf(" The reversed string - %s ",words);
return 0;

}

void reverse(char *p)
{
int l=strlen(p),i,m=l/2;
   char temp;
   l--;
   for(i=0;i<m;i++)
   {
       temp=p[i];
       p[i]=p[l];
       p[l]=temp;
       l--;
   }
}

Here reverse(char *p) function reverses the whole string p and logic behind this
function is as follows -

initially l contains the size of string p, as starting index of an array is 0 (zero)
so that the last charecter is in the index (l-1) and for this reason I have decremented the value
of l before for loop.

Value of m indicates the middle of the string p.

In the for loop i initialized with value 0 that the starting index of the string
and l points to the last index of the string.
In each iteration of the for loop I have interchanged the charecter at index i with the charecter
at index l and vice-versa.
At the end of the loop l is decremented by 1 and i incremented by 1 and this for repeates until we
have not reached the middle of string that is (m-1) as index starts from 0 instead of 1.

At the end of this for loop the whole string is reversed.

Change your reverse function with this reverse function.

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