class MyQueue {
public:
/** Initialize your data structure here. */
stack<int> s1,s2;
MyQueue() {
}
/** Push element x to the back of queue. */
void push(int x) {
s1.push(x);
}
/** Removes the element from in front of queue and returns that element. */
int pop() {
while(s1.size()>1) s2.push(s1.top()),s1.pop();
int t=s1.top();
s1.pop();
while(s2.size()) s1.push(s2.top()),s2.pop();
return t;
}
/** Get the front element. */
int peek() {
while(s1.size()>1) s2.push(s1.top()),s1.pop();
int t=s1.top();
while(s2.size()) s1.push(s2.top()),s2.pop();
return t;
}
/** Returns whether the queue is empty. */
bool empty() {
return s1.empty();
}
};
/**
* Your MyQueue object will be instantiated and called as such:
* MyQueue obj = MyQueue();
* obj.push(x);
* int param_2 = obj.pop();
* int param_3 = obj.peek();
* bool param_4 = obj.empty();
*/
leecode
官网更新最新的思路差不多
class CQueue {
public:
stack<int>s1,s2;
CQueue() {
}
void appendTail(int value) {
s1.push(value);
}
int deleteHead() {
if(s2.empty())
{
while(!s1.empty())
{
s2.push(s1.top());
s1.pop();
}
}
if(s2.empty())
{
return -1;
}
else
{
int t=s2.top();
s2.pop();
return t;
}
}
};
/**
* Your CQueue object will be instantiated and called as such:
* CQueue* obj = new CQueue();
* obj->appendTail(value);
* int param_2 = obj->deleteHead();
*/
新链接:https://leetcode-cn.com/problems/yong-liang-ge-zhan-shi-xian-dui-lie-lcof/