Chapter 21, Problem 3FTE

Explanation of Solution

Program purpose:

The given program is used to implement stack using linked list.

Logical error:

Logical error is a mistake in a program’s source code that leads to produce an incorrect output. This error is a type of run time error, as it cannot be identified during the compilation of the program. This is a logical mistakes created by the programmer and it is determined when the program produces wrong output.

Error in the given code:

The function “pop()” forgets to remove the value from the stack. That is the statement for removing the element is missing in the function definition. The below given statement should be added in the function definition to produce the correct output.

Correct statement:

/*creates a string variable retValue which holds value of the top element*/

String retValue=top.value;

//assigning the top with the link of next node of the list

top=top.next;

//returning the value at position top in the stack

return retValue;

Corrected code:

/*pop method removes the value from the top position of the stack*/

int pop()

{

/*condition for checking whether the stack is empty*/

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