GATE CS 1998

Question 81

Draw the binary tree with node labels a, b, c, d, e, f and g for which the inorder and postorder traversals result in the following sequences:

Inorder       a f b c d g e
Postorder     a f c g e d b

Question 82

What is the result of the following program?

program side-effect (input, output);
    var x, result: integer;
    function f (var x:integer):integer;
    begin
        x:x+1;f:=x;
    end;
begin
    x:=5;
    result:=f(x)*f(x);
    writeln(result);
end;

• 5
• 25
• 36
• 42

Question 83

A counting semaphore was initialized to 10. Then 6 P (wait) operations and 4 V (signal) operations were completed on this semaphore. The resulting value of the semaphore is

• 0

• 8

• 10

• 12