10. bool Stack::push(int n)‏ { if (! isFull() ) { stackArray[stk_ptr] = n; stk_ptr = stk_ptr + 1; return true; } else return false; } bool Stack::pop(int &n)‏ { if (! IsEmpty ()) { stk_ptr = stk_ptr – 1; n = stackArray[stk_ptr]; return true; } else return false; } bool Stack::isEmpty()‏ { return (stk_ptr == 0); } Stack::Stack(int s)‏ { maxSize = s; stk_ptr = 0; stackArray = new int[maxSize]; } bool Stack::isFull()‏ { return (stk_ptr == maxSize); }

22. Circular Implementation bool Queue::remove(int &n)‏ { if (! isEmpty() { n = QueueArray[front]; front++; if (front == maxSize) front = 0; size--; return true; } else return false; } 0 1 2 3 MS-1

31. Evaluation of Fully Parenthesized Expression (a+(b/c)) Assuming a=2, b=6, c=3 Pop”(a+2” and evaluate and push the result back 4 )‏ Pop”(b/c” and evaluate and push the result back (a+2 )‏ Push (a+(b/c c push (a+(b/ / push (a+(b b push (a+( ( push (a+ + push (a a Push ( ( Remarks Stack Input Symbol

33. INFIX and POSTFIX abc/eg+*+h+fi*- a+b/c*(e+g)+h-f*i ab/c-de*+ac*- a/b-c+d*e-a*c ab+cd+*e/f- (a+b)*(c+d)/e-f ab*cd*+ a*b+c*d abc*+ a+b*c Postfix Infix

35. Algorithm to Evaluate Expressions in RPN (a+b)*(c+d)  ab+cd+* Assuming a=2, b=6, c=3, d=-1 Pop 8 and 2 from the stack, multiply, and push the result back. Since this is end of the expression, hence it is the final result. 16 * Pop c and d from the stack, add, and push the result back 8 2 + Push 8 c d d Push 8 c c Pop a and b from the stack, add, and push the result back 8 + Push a b b Push a a Remarks Stack Input Symbol

37. Converting Infix to RPN (a+b)*(c+d)  ab+cd+* Pop remaining symbols from the stack and display RPN  a b + c d + * End of input Pop till “(” is found and display – RPN  a b + c d + * )‏ Operand – display – RPN  a b + c d * ( + d Push as + has higher precedence than ( * ( + + Operand – display – RPN  a b + c * ( c Push * ( ( Push as stack is empty * * Pop till “(” is found and display – RPN  a b + )‏ Operand – display – RPN  a b ( + b Push as + has higher precedence than ( ( + + Operand – display – RPN  a ( a Push ( ( Remarks Stack Input Symbol

38. a+b*c/(d+e)  a b c * d e + / + Pop till “(” is found – RPN  a b c * d e + + / )‏ Pop remaining symbols from the stack and display RPN  a b c * d e + / + End of input Operand – display – RPN  a b c * d e + / ( + e Push as + has higher precedence than ( + / ( + + Operand – display – RPN  a b c * d + / ( d Push + / ( ( Pop * and push / as * and / have the same precedence but / has higher precedence than + – RPN  a b c * + / / Operand – display – RPN  a b c + * c Push as * has higher precedence than + + * * Operand – display – RPN  a b + b Push as stack is empty + + Operand – display – RPN  a a Remarks Stack Input Symbol

41. Activation Records