Question

C++

Write a program that reads a line of text, changes each uppercase letter to lowercase, and places each letter both in a queue and onto a stack. The program should then verify whether the line of text is a palindrome (a set of letters or numbers that is the same whether read forward or backward). Please use a Queue Class and Stack class.

Answer 1

------------------MyQueue.h----------------

#include<iostream>

using namespace std;

class MyQueue

{

    char *queue;

    int front;

    int rear;

    int max;

   

    public:

       

        MyQueue(int max)

        {

            this->max = max;

           

            // create an int array os size max

            this->queue = new char[ max ];

           

            this->front = -1;

            this->rear = -1;

        }

       

        // destructor

        ~MyQueue()

        {

            delete this->queue;

        }

       

        void enqueue(char i)

        {

            // if the queue is full

            if( rear == max - 1 )

                return;

            else

            {

                // add element to queue

                this->queue[++this->rear] = i;

            }

        }

       

        void dequeue()

        {

            // if queue is empty

            if( this->front != this->rear )

                this->front++;

        }

       

        char top()

        {

            // if queue is empty

            if( this->front == this->rear )

                return -1;

            else

                return this->queue[ this->front + 1 ];

        }

       

        // check if queue is empty

        bool isEmpty()

        {

            return this->front == this->rear;

        }

};

---------------------Stack.h---------------------

#ifndef MY_STACK

#define MY_STACK

#include<iostream>

#include<cstdlib>

#include<cstring>

using namespace std;

class Stack

{

    // declare stack array arr

    char *arr;

   

    // to store the index of the top most element

    int top;

   

    // to store the current capacity of arr

    int size;

   

    public:

       

        // constructor

        Stack();

       

        // constructor

        Stack(int);

       

        // destructor

        ~Stack();

       

        // function to check if the stack is empty

        bool isEmpty();

       

        // function to check if the stack is full

        bool isFull();

       

        // push element intot the stack

        void push(char);

        

        // return the top most element in the stack

        char peek();

       

        // pop element from stack

        void pop();

       

        // resize the array to double the original capacity

        void resize();

       

        // display contents of stack

        void view();

};

#endif

-------------------Stack.cpp--------------------

#include "Stack.h"

// constructor

Stack::Stack()

{

    // declare an array of size 4

    arr = new char[4];

       

    // set initial capacity to 4

    size = 4;

       

    top = -1;

}

// constructor

Stack::Stack(int new_size)

{

    // declare an array of size new_size

    arr = new char[new_size];

       

    // set initial capacity to new_size

    this->size = new_size;

       

    top = -1;

}

// destructor

Stack::~Stack()

{

    delete arr;

    size = 0;

    top = -1;

}

// function to check if the stack is empty

bool Stack::isEmpty()

{

    if(top == -1)

        return true;

    return false;

}

// function to check if the stack is full

bool Stack::isFull()

{

    if(top == size - 1)

        return true;

    return false;

}

void Stack::push(char n)

{

    // if stack is full

    if(isFull())

        // resize the array to double the original capacity

        resize();

       

    arr[++top] = n;

}

// return the top most element in the stack

char Stack::peek()

{

    if(isEmpty())

        return -1;

       

    return arr[top];

}

// pop element from stack

void Stack::pop()

{

    // if stack is empty

    if(isEmpty())

        cout<<"The stack is alreasy empty";

   

    // remove the top most element of the stack

    top--;

}

// resize the array to double the original capacity

void Stack::resize()

{

    // create a new int array double the size of arr

    char *temp = new char[2 * size];

    int i;

   

    for( i = 0 ; i < size ; i++ )

        // cop contents of arr to temp

        temp[i] = arr[i];

   

    // set capacity to double the original capacity

    size *= 2;

   

    // set temp as the new stack array

    arr = temp;

}

// display contents of stack

void Stack::view()

{

    int i;

   

    for( i = 0 ; i <= top ; i++ )

        cout<<arr[i]<<" ";

       

    cout<<endl;

}

-------------------main.cpp----------------

#include "Stack.cpp"

#include "MyQueue.h"

#include<bits/stdc++.h>

bool isPalindrome()

{

    // remains true is string is palindrome

    bool flag = true;

       

    // create queue of size 10000

    MyQueue q(10000);

   

    Stack st;

    string temp;

   

    cout<<"Enter string ; ";

   

    // read complete line

    getline( cin , temp );

   

    // convert string to lower case

    transform(temp.begin(), temp.end(), temp.begin(), ::tolower);

   

    int i, len = 0;

   

    for( i = 0 ; i < temp.length() ; i++ )

    {

        // if the current character is not space

        if( temp[i] != ' ' )

        {

            // convert the current character to lower case and addd to queue

            q.enqueue((char)tolower(temp[i]));

           

            // convert the current character to lower case and addd to stack

            st.push((char)tolower(temp[i]));

        }

    }

    // loop untill the queue is empty

    while( !q.isEmpty() )

    {

        char ch1 = q.top();

        char ch2 = st.peek();

       

        q.dequeue();

        st.pop();

       

        if( ch1 != ch2 )

       {

            flag = false;

           

            break;

        }

    }

       

    return flag;

}

int main()

{

    if( isPalindrome() )

        cout<<"It is palindrome.";

    else

        cout<<"it is not palindrome.";

       

    return 0;

}

Sample Output