Addition, Subtraction, Multiplication, Division, all performed within a program by users choice. If result is <= 100 then message shown is centuary or above. Using Switch Case. Can any one help me with this program plz???

Here is Syntax for Switch

switch (expression)
{
   case constant-expression:
      statement
      jump-statement
   [default:
      statement
      jump-statement]
}

In your case it will be like this

swith(result){
case 100: showMessage("Some Message"); break;
default : showMessage("No Match Found");
}

//----------- Default case show when no matching case found in swith statement.