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Problem of the day

You will be given ‘Q’ queries. You need to implement a queue using two stacks according to those queries. Each query will belong to one of these three types:

```
1 ‘X’: Enqueue element ‘X’ into the end of the nth queue. Returns true after the element is enqueued.
2: Dequeue the element at the front of the nth queue. Returns -1 if the queue is empty, otherwise, returns the dequeued element.
```

```
Enqueue means adding an element to the end of the queue, while Dequeue means removing the element from the front of the queue.
```

Detailed explanation

```
1 <= Q <= 10^5
1 <= P <= 2
1 <= X <= 10^5
Time limit: 1 sec
```

```
7
1 2
1 3
2
1 4
1 6
1 7
2
```

```
True
True
2
True
True
True
3
```

```
For this input, we have the number of queries, 'Q' = 7.
Operations performed on the queue are as follows:
push(2): Push element ‘2’ into the queue. This returns true.
push(3): Push element ‘3’ into the queue. This returns true.
pop(): Pop the top element from the queue. This returns 2.
push(4): Push element ‘4’ into the queue. This returns true.
push(6): Push element ‘6’ into the queue. This returns true.
push(7): Push element ‘7’ into the queue. This returns true.
pop(): Pop the top element from the queue. This returns 3.
```

```
7
1 11
1 51
1 26
2
1 6
2
2
```

```
True
True
True
11
True
51
26
```

```
For this input, we have the number of queries, Q = 7.
Operations performed on the queue are as follows:
push(11): Push element ‘11’ into the queue. This returns true.
push(51): Push element ‘51’ into the queue. This returns true.
push(26): Push element ‘26’ into the queue. This returns true.
pop(): Pop the top element from the queue. This returns 11.
push(6): Push element ‘6’ into the queue. This returns true.
pop(): Pop the top element from the queue. This returns 51.
pop(): Pop the top element from the queue. This returns 26.
```