Pointers stuff

getting trouble with this program.
trying to return a reverse string to main but it doesn't work.
when I put the function into main it works.
I think I'm not using the correct way dealing with pointers.
What am I doing wrong?

Code:

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#include <stdio.h>#include <stdlib.h>
#include <string.h>
char * rev(char * word);
int main()
{
      char word1[100];
      char rev1[100];
      printf("Enter a word");
      scanf("\n%s",word1);
      strcpy(rev1,rev(word1));
      printf("\nThe reverse order of this word is: %s",rev1);
      return 0;




}
char * rev(char * word)
{
    int len=strlen(word);


    char reverse[len];
    int j=0;
    for(int i=len-1;i>=0;i--)
    {
          reverse[i]=word[j];
          ++j;
    }
    reverse[len]='\0';
    return reverse;
}

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There are two (or 3) things wrong with your rev function.
1. Your local reverse array is too short (there is no room for a \0)
2. Your local array goes out of scope when you return. You don't return arrays, you return only pointers.
3. Only C99 supports variable length arrays.

Assuming you want to keep the original string, you need something like this.

Code:

---

char *rev(const char *word, char *reverse) {
  // your existing logic
  return reverse;
}

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Shouldn't this post be in the C section? It's not C++.

Quote:

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Originally Posted by thmm

Shouldn't this post be in the C section? It's not C++.

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Yes, moved.

Quote:

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Originally Posted by Salem

There are two (or 3) things wrong with your rev function.
1. Your local reverse array is too short (there is no room for a \0)
2. Your local array goes out of scope when you return. You don't return arrays, you return only pointers.
3. Only C99 supports variable length arrays.

Assuming you want to keep the original string, you need something like this.

Code:

---

char *rev(const char *word, char *reverse) {
  // your existing logic
  return reverse;
}

---

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thank u for helping -now it works
:biggrin: