converting two strings to upper and lower case using a function

[hummingdev]

Hi all , hope you're well



My code so far

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


void uplostr(char *s1, char *s2)




int main()
{
  char  string1[] = "My NaMe Is SJaD";
  char  string2[] = "My NaMe Is SJaD";


  printf(" Uppercase : %s \n Lowercase : %s\n\n",uplostr(string1),uplostr(string2));




  return 0;
}


void uplostr(char *s1, char *s2)
{
    char  *p;
    char  *p2;




  for (*p=s1; *p != '\0'; p++)
  {
    *p=toupper(*p);
  }


  for (*p2=s2; *p2 != '\0'; p2++)
  {
    *p2 = tolower(*p2);
  }
   return;
}

I keep getting these 3 errors and I have now idea how to deal with them :
error expected '=', ',', ';', 'asm' or '__attribute__' before '{' token|.
error  expected '=', ',', ';', 'asm' or '__attribute__' before '{' token|.
error expected '{' at end of input|.

any hits would be appreciated :)

[laserlight]

You're missing the terminating semi-colon on this line:

void uplostr(char *s1, char *s2)

You're calling uplostr wrongly here:

printf(" Uppercase : %s \n Lowercase : %s\n\n",uplostr(string1),uplostr(string2));

I would expect:

uplostr(string1, string2);
printf(" Uppercase : %s \n Lowercase : %s\n\n", string1, string2);

In the implementation of uplostr, you don't actually need p and p2 because you can use s1 and s2 directly. If you do want to use p and p2, then you need to be careful how you set the value of the pointer (not just what the pointer points to).

[hummingdev]

thanks for the repley laserlight

I took your advice and change the code accordingly but the out put prints the string the same as it as without changing the case

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


void uplostr(char *s1, char *s2);




int main()
{
  char  string1[] = "My NaMe Is SJaD";
  char  string2[] = "My NaMe Is SJaD";
    uplostr(string1,string2);
  printf(" Uppercase : %s \n Lowercase : %s\n\n",string1,string2);




  return 0;
}


void uplostr(char *s1, char *s2)
{
    int i,j;


  for (i=0; i != '\0'; i++)
  {
    *s1=toupper(*(s1+i));
  }


  for (j=0; j != '\0'; j++)
  {
    *s2 = tolower(*(s2+i));
  }
   return;
}

[laserlight]

*s1 is equivalent to s1[0]. In other words, you're only changing the first element on every iteration of the array. Rather, make use of s1 in the same way as you did with p in your previous attempt. You do not need those array indices since you are going to use pointer notation only.

If you want to use *(s1+i), then you might as well use s1[i] because it is likely to be easier to understand.

[hummingdev]

I understand now, thanks
I followed your advice and the code works perfect


you're a life saver laser <3