Implement a fixed-size queue data structure that stores integers. The queue should have a maximum size and support enqueue and dequeue operations. Return -1 when trying to dequeue from an empty queue or enqueue to a full queue.
Examples:
Input: operations = [
'enqueue 1', // returns 1
'enqueue 2', // returns 2
'enqueue 3', // returns -1 (queue is full, size=2)
'dequeue', // returns 1
'enqueue 3', // returns 3
'dequeue' // returns 2
]
maxSize = 2
Output: [1, 2, -1, 1, 3, 2]
Explanation: Queue operations with max size 2, showing return values for each operation
Input: operations = [
'dequeue', // returns -1 (empty queue)
'enqueue 1', // returns 1
'dequeue' // returns 1
]
maxSize = 1
Output: [-1, 1, 1]
Explanation: Queue operations with max size 1, starting with dequeue on empty queue
Method used to process your code
public static List<Integer> processQueueOperations(List<String> operations, Integer maxSize) {
FixedSizeQueue queue = new FixedSizeQueue(maxSize);
List<Integer> results = new List<Integer>();
for (String operation : operations) {
if (operation.startsWith('enqueue')) {
Integer item = Integer.valueOf(operation.split(' ')[1]);
results.add(queue.enqueue(item));
} else if (operation == 'dequeue') {
results.add(queue.dequeue());
}
}
return results;
}
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