C program to check whether the entered character is a alphabet or a number

#include<stdio.h>
#include<conio.h>
void main()
{
char a;
puts("Enter the character");
scanf("%c",&a);
if(a>=48&&a<=57)
printf("%c is number\n",a);
else if(a>=65&&a<=90)
printf("%c is upper case alphabet\n",a);
else if(a>=97&&a<=122)
printf("%c is lower case alphabet\n",a);
else
printf("%c is neither number nor alphabet\n",a);
}