Question

Write a simple program in C++ 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). DO NOT USE THE STACK LIBRARY, QUEUE LIBRARY, OR ANY OTHER LIBRARIES NOT COVERED YET.

Answer 1

CODE:

#include<iostream>
#include<string>
#define MAX 100
using namespace std;
char S[MAX],Q[MAX];
int top=-1,front=-1,rear=-1;
void push(char ch)      //function for stack push operation
{
   top=top+1;
   S[top]=ch;
}
char pop()           //function for stack pop operation
{
   char ele;
   if(top==-1)
       return -1;
   else
   {
       ele=S[top];
       top=top-1;
       return ele;
   }
      
}
bool isEmpty()   //function for checking stack is empty or not
{
   if(top==-1)
   {
       return true;
   }
   else
   {
       return false;
   }
}
void enque(int x)   //function for queue enqueue operation
{
    if(rear==MAX-1)
        printf("QUEUE IS OVERFLOWED:");
    else
    {
        rear=rear+1;
        Q[rear]=x;
        if(rear==0)
            front=0;

    }

}
char deque()    //function for queue dequeue operation
{
   char ele;
    if(front==-1 || front>rear)
        printf("QUEUE IS UNDERFLOWED:");
    else
    {
       ele=Q[front];
        front=front+1;
        return ele;

    }

}
int main()
{
   string text,text1;
   int pal_length=0;
   char stack_element,queue_element;
   cout<<"Enter the text: ";
   getline(cin,text);
   text1=text;
   for(int i=0;i<text.length();i++) //logic for coverting string to lowercase
   {
       if(text[i]>='A' && text[i]<='Z')
       {
           text[i]=text[i]+32;
       }
   }
   for(int i=0;i<text.length();i++)
   {
       push(text[i]);         //placing each character of a string in stack and queue
       enque(text[i]);
   }
   while(!(isEmpty()))
   {  
       stack_element=pop();     //popping element from stack
       queue_element=deque();   //dequeuing element from queue
       if(stack_element==queue_element)   //comparing elements
       {
           pal_length=pal_length+1;
       }
   }
   if(pal_length==text.length())
   {
       cout<<"The text "<<text1<<" is a palindrome"<<endl;
   }
   else
   {
       cout<<"The text "<<text1<<" is not a palindrome"<<endl;
   }  
}

OUTPUT:

Enter the text: LeveL The text LeveL is a palindrome

Enter the text: Stanley Yelnats The text Stanley Yelnats is a palindrome