C Program - Write a program, which accepts a character from the user and checks if it is an alphabet, digit or punctuation symbol. If it is an alphabet, check if it is uppercase or lowercase and then change the case.

Program

#include<stdio.h>
int main()
{
    char ch;
    printf("Enter Character : ");
    scanf("\n %c",&ch);
    if((ch>=65 && ch<=90 )|| (ch>=97 && ch<=122))
    {
        printf("\nIt is an Alphabet.:");
if(isupper(ch))
{
ch=tolower(ch);
printf("%c",ch);
}
else
{
ch=toupper(ch);
printf("%c",ch);
}
    }
    if(ch>=48 && ch<=57)
    {
        printf("\n'%c' is Digit.",ch);
    }
    if((ch>=58 && ch<=64) || (ch>=91 && ch<=96) || (ch>=33 && ch<=47) || (ch>=123 && ch<=126))
    {
        printf("\n'%c' is Punctuation Symbol.",ch);
    }
    return 0;
}

Output:

Enter Character : r

It is an Alphabet.:R