cpp-data-structures/queue.cpp at main · gkumar9891/cpp-data-structures · GitHub

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#include<iostream>
#definequeueSize2

usingnamespacestd;

classqueue {
public:

// structure of queue
int *arr = newint[queueSize];
int front = -1;
int back = -1;


//insertion in queue
voidenqueue(int data) {
if(front == -1) {
 front++;
 }

if(back == queueSize - 1) {
 cout << "insertion in queue not possible";
return;
 }

 back++;
// *(arr + back) = data; // array in pointer
 arr[back] = data;
 }

//current element in queue
voidpeek() {
 cout << *(arr + front);
 }

//deletion in queue
voiddequeue() {
if(front == -1) {
 cout << "dequeue is not possible";
return;
 }
 front++;
 }

//check for the container
boolempty() {
if(front > back || front == -1) {
returntrue;
 }
returnfalse;
 }
};

intmain() {

 queue list;
 list.enqueue(1);
 list.dequeue();
 list.enqueue(2);

// list.dequeue();

 list.peek();
// cout << list.empty();
return0;
}