To distinguish whether the number is alphabet, number or special character

#include<stdio.h>
#include<conio.h>
int main(void)
{
    unsigned char a;
    printf("Enter Character : ");
    a = getche();
    if((a>64 && a<91) || (a>96 && a<123))
    {
        printf("Alphabet");
    }
    else if(a>47 && a<58)
    {
        printf("Number");
    }
    else
    {
        printf("Special Character");
    }
    return 0;
}

To Print first 100 even numbers

#include<stdio.h>
#include<conio.h>
int main(void)
{
int i,num;
int res=1;
printf("Enter Number : \t");
scanf("%d",&num);
for(i=num; i>1; i--)
{
res*=i;
}
printf("\n\nFactorial of %d is : %d",num,res)
getch();
return 0;
}

To print first 100 odd numbers

#include<stdio.h>
#include<conio.h>
int main(void)
{
  int i;
  printf("First 100 natural odd numbers are : \t");
for(i=1; i<200; i++)
{
      if(i%2==1)
printf("%d,\t",i);
}
getch();
return 0;
}

Greater number among two variables

#include<stdio.h>
#include<conio.h>
int main(void)
{
   int x,y,z;
   printf("\nEnter First Number : ");
   scanf("%d",&x);
   printf("\nEnter Second Number : ");
   scanf("%d",&y);
   if(x>y)
   {
      printf("%d is greater than %d",x,y);
   }
   else if(y>x)
   {
      printf("%d is greater than %d",y,x);
   }
   else
   {
      printf("Both Numbers are equal");
   }
   return 0;
}