像数组一样访问 c++ 队列元素

可以像数组一样访问队列元素吗?如果不是，那有什么类似于队列的容器可以呢?

解决方案

这是一个非常适合 std::deque.它针对添加/删除到末尾进行了优化，但也提供了对中间元素的随机访问.引用链接的文章:

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双端队列非常像vector:和vector一样，是一个序列支持随机访问元素，恒定时间插入和删除末尾的元素序列，以及中间元素的线性时间插入和移除.

... deque 还支持在序列的开头以恒定时间插入和删除元素

因此，由于它可以有效地从两端添加/删除，因此 deque 可以通过其 push_back 和 pop_front 方法有效地用作队列:

std::deque双端队列；//入队aDeque.push_back(1);aDeque.push_back(2);//出队int top = aDeque.front();aDeque.pop_front();

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像数组一样访问元素意味着使用下标运算符

deque也支持通过下标操作符随机访问:

std::cout <<aDeque[0];

Can queue elements be accessed like an array? If not, then what containers similar to a queue can?

解决方案

This is a task ideal for std::deque. Its optimized for adding/removing onto the end but also provides random access to elements in the middle. To quote the linked article:

A deque is very much like a vector: like vector, it is a sequence that supports random access to elements, constant time insertion and removal of elements at the end of the sequence, and linear time insertion and removal of elements in the middle.

... deque also supports constant time insertion and removal of elements at the beginning of the sequence

So because it can efficiently add/remove from both ends, deque can be used efficiently as a queue with its push_back and pop_front methods:

std::deque<int> aDeque;

// enqueue
aDeque.push_back(1);
aDeque.push_back(2);

// dequeue
int top = aDeque.front();
aDeque.pop_front();

Accessing elements like an array means using the subscript operator

deque also support the random access through the subscript operator:

std::cout << aDeque[0];