WAP to write character into file in lower case and display from file in uppercase

Defination:: WAP to write character into file in lower case and display from file in uppercase

Source Code ::

#include<stdio.h>
#include<conio.h>
void main()
{
    FILE *f;
    char ch;
    clrscr();
    f=fopen("test.txt","w");
    while((ch=getchar())!=EOF)
    {

        putc(ch,f);

    }
    fclose(f);
    f=fopen("test.txt","r");
    while((ch=getc(f))!=EOF)
    {
        printf("%c",ch-32);
    }
    fclose(f);
    getch();
}