ReZero's Utopia.

Implement Stack using Queues

字数统计: 139阅读时长: 1 min
2019/07/30 Share

Implement the following operations of a stack using queues.

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class MyStack {
public:

queue<int> q;
/** Initialize your data structure here. */
MyStack() {
}

/** Push element x onto stack. */
void push(int x) {
q.push(x);
for(int i = 1; i < q.size(); ++i) {
q.push(q.front());
q.pop();
}
}

/** Removes the element on top of the stack and returns that element. */
int pop() {
int top = q.front();
q.pop();
return top;
}

/** Get the top element. */
int top() {
return q.front();
}

/** Returns whether the stack is empty. */
bool empty() {
return q.empty();
}
};

/**
* Your MyStack object will be instantiated and called as such:
* MyStack* obj = new MyStack();
* obj->push(x);
* int param_2 = obj->pop();
* int param_3 = obj->top();
* bool param_4 = obj->empty();
*/
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