If you use a function like fgets this will help you do what you want. Then you just have to inspect the contents of the string for the characters, e.g.
Code:
if (inputstr[0]>='0' && inputstr[0]<='9')
  printf("You entered a number\n");
else if (inputstr[0]>='A' && inputstr[0]<='Z')
  printf("You entered a capital letter\n");