Write a c plus plus program using queue operation?

Answer 1

A queue is a first-in-first-out (FIFO) list of elements. In C++, you could implement a queue by designing a queue class that provided a constructor, destructor, add, and remove methods. The private implementation could use an array, with size specified in the constructor. It would have pointers or indicies that "follow each other" around the array. At boundary state, the queue::add() method would either throw a queue full exception, or it could dynamically adjust the array size, and the queue:remove() method would return null or throw a queue empty exception. Other implementations could be used, such as a singly or doubly linked list, but the "cost" of constantly allocating and deallocating elements would seem to overwhelm the simplicity of the array approach, even considering the possibility of (intermittantly) increasing the allocated size. No matter what approach is used, the public interface should be stable and well defined, so that various internal approachs could be tried and evaluated.

Answer 2

#include
#include


template
class queue
{
private:
std::list data;
public:
void push (const T& val) { data.push_back (val); }
void pop () { data.pop_front (); }
const T& front () { return data.front(); }
const size_t size () const { return data.size(); }
};


int main()
{
queue q;


size_t loop = 0;
while (loop != 10)
q.push (++loop);


while (loop--)
{
std::cout << q.front() << std::endl;
q.pop();
}
}

Answer 3

#include<iostream>

#include<queue>

#include<stack>

int main()

{

std::queue<int> q;

std::stack<int> s;

for (int i=0; i!=10; ++i)

{

q.push (i);

s.push (i);

}

std::cout << "Queue\tStack\n";

for (int i=0; i!=10; ++i)

{

std::cout << q.front() << '\t' << s.top() << '\n';

q.pop();

s.pop();

}

}