#include<stdio.h>
#include<conio.h>
#include<string.h>
void
main()
{
char
s1[20];
clrscr();
printf("\n
enter a string with upper and lowercase letters");
gets(s1);
printf("\The
string after converting to uppercase\t%s",strupr(s1));
printf("\n
The string after converting to lowercase\t%s",strlwr(s1));
getch();
}
/*Output
enter a string with upper and lowercase
letters IndIA
The string after
converting to uppercase INDIA
The string after converting to lowercase india */
