Question

I made a program which removes spaces and makes a string upper case by preprocessor directives .its not changing to uppercase

#include <stdio.h>
#include <conio.h>
# define TOUPPER(x) (x-32)
void main(void)
{
    int i,j;
    char str[100],*p;
    clrscr();
    printf("Enter the string:\n");
    gets(str);
    for(i=0;    ;i++)
    {
        if(str[i]=='\0')
        break;
        if(str[i]==' ')
        {
            for(j=i;    ;j++)
            {
             str[j]=str[j+1];
             if(str[j]=='\0')
             break;
            }
         }
         if(str[i]<='a'||str[i]>='z')
         {
            *p=str[i];
            TOUPPER('p');

         }


        }
        puts(str);
    getch();
}

Answer 1

Its because you do

TOUPPER('p');

and it is defined as

(x-32)

This changes ‘p’ to upper-case but don’t save it.

You need to change you define like this

#define TOUPPER(x) ((*x)=((*x)-32))

just do call it like this:

TOUPPER(p);