Description

A stack is an abstract data type that serves as a collection of elements, where a node can be added to a stack and removed from a stack only at its top. Two principal operations can be used to manipulate a stack: push, which adds an element at the top, and pop, which removes the element at the top of the collection.

Let’s see how the stack data structure can be realized in C++.We have an approach to implement stack: linked list. Thus, we define a class as follows:

class List_stack {

    public:

        List_stack();

        ~List_stack();

        void push(const int &);

        void pop();

        void print();

    private:

        ListNode *head;

        ListNode *tail;

};

where List_stack implements the stack data structure

 

REQUIREMENTS:

Implement the constructor, destructor, push(), pop() and print() member functions of List_stack classes.

Note:

1.This problem involves three files.

• function.h: Class definitions.
• function.cpp: Member-function definitions.
• main.cpp: A driver program to test your class implementation.

You will be provided with main.cpp and function.h, and asked to implement function.cpp.

function.h

#ifndef FUNCTION_H #define FUNCTION_H #include <iostream> class ListNode { friend class List_stack; //make List_stack a friend public: ListNode( const int &info ) //constructor : data( info ), nextPtr( NULL ), prevPtr( NULL ) { } //end ListNode constructor private: int data; //data ListNode *nextPtr; // next node in list ListNode *prevPtr; }; //end class ListNode class List_stack { public: List_stack(); ~List_stack(); void push(const int &); void pop(); void print(); private: ListNode *head; ListNode *tail; }; #endif // FUNCTION_H

main.cpp

#include<iostream> #include<string.h> #include "function.h" using namespace std; int main(){ List_stack L_stack; char command[10]; int n; while(cin>>command){ if(strcmp(command,"pop")==0){ L_stack.pop(); }else if(strcmp(command,"push")==0){ cin >> n; L_stack.push(n); }else if(strcmp(command, "print") == 0){ L_stack.print(); cout << endl; } } return 0; }

2.For OJ submission:

       Step 1. Submit only your function.cpp into the submission block.

       Step 2. Check the results and debug your program if necessary.

Input

There are three kinds of commands:

• “push integerA” represents adding an element with int value A at the top of the stack.
• “pop “ represents removing the element at the top of the stack.
• “print” represents showing the current content of the stack.

Each command is followed by a new line character.

Input terminated by EOF.

Output

The output should consist of the current state of the stack.

When the stack is empty, you don’t need to print anything except a new line character.

Sample Input  Download

Sample Output  Download

Partial Judge Code

10998.cpp

Partial Judge Header

10998.h

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Description

Given a set of strings, perform the operations according to the following commands.

 

Commands: (n will not be equal to m)

s n m:

Swap the n^th string and the m^th string.

i n m:

Insert the m^th string at the tail of the n^th string.

si n m:

Swap the specified strings first, and then insert.

is n m:

Insert first, and then swap the two specified strings.

t n m:

If the n^th string is equal to the m^th string, do i n m. Otherwise, do s n m.

e:

Exit.

 

Note:

You will be provided with main.cpp and function.h, and asked to implement function.cpp including

Str::Str(char*);

Str::Str(const Str &);

bool Str::operator==( const Str &) const;

 

 

Input

The first line is an integer N indicating the number of input strings.

The following N lines each contains one input string.

Starting from the N+2^th line will be a sequence of commands.

Output

Output the final result of the input strings.

Sample Input  Download

Sample Output  Download

Partial Judge Code

11431.cpp

Partial Judge Header

11431.h

Tags

Discuss