How to implement stack using queue and vice versa

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To implement a stack using a queue, we can use two queues. To implement a queue using a stack, we can use two stacks.

To implement a stack using a queue, we can use two queues. One queue will act as the main stack, while the other will be used for temporary storage during push operations.
For example, when pushing an element onto the stack, we can dequeue all elements from the main queue and enqueue them into the temporary queue. Then, we enqueue the new element into the main queue and enqueue all elements from the temporary queue back into the main queue.
To implement a queue using a stack, we can use two stacks. One stack will act as the main queue, while the other will be used for temporary storage during enqueue and dequeue operations.
For example, when enqueueing an element into the queue, we can push the element onto the temporary stack. When dequeuing an element from the queue, we can pop all elements from the main stack onto the temporary stack, pop the top element from the temporary stack, and then push back all elements from the temporary stack onto the main stack.

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