[leetcode]641. Design Circular Deque

[leetcode]641. Design Circular Deque

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Analysis

年纪大了换季就会感冒—— [ummmm~]

Design your implementation of the circular double-ended queue (deque).
Your implementation should support following operations:
MyCircularDeque(k): Constructor, set the size of the deque to be k.
insertFront(): Adds an item at the front of Deque. Return true if the operation is successful.
insertLast(): Adds an item at the rear of Deque. Return true if the operation is successful.
deleteFront(): Deletes an item from the front of Deque. Return true if the operation is successful.
deleteLast(): Deletes an item from the rear of Deque. Return true if the operation is successful.
getFront(): Gets the front item from the Deque. If the deque is empty, return -1.
getRear(): Gets the last item from Deque. If the deque is empty, return -1.
isEmpty(): Checks whether Deque is empty or not.
isFull(): Checks whether Deque is full or not.
设计双向循环链表，用vector实现~

Implement

class MyCircularDeque {
public:
    /** Initialize your data structure here. Set the size of the deque to be k. */
    MyCircularDeque(int k) {
        size = k;
    }

    /** Adds an item at the front of Deque. Return true if the operation is successful. */
    bool insertFront(int value) {
        if(isFull())
            return false;
        myque.insert(myque.begin(), value);
        return true;
    }

    /** Adds an item at the rear of Deque. Return true if the operation is successful. */
    bool insertLast(int value) {
        if(isFull())
            return false;
        myque.push_back(value);
        return true;
    }

    /** Deletes an item from the front of Deque. Return true if the operation is successful. */
    bool deleteFront() {
        if(isEmpty())
            return false;
        myque.erase(myque.begin());
        return true;
    }

    /** Deletes an item from the rear of Deque. Return true if the operation is successful. */
    bool deleteLast() {
        if(isEmpty())
            return false;
        myque.pop_back();
        return true;
    }

    /** Get the front item from the deque. */
    int getFront() {
        if(isEmpty())
            return -1;
        return myque[0];
    }

    /** Get the last item from the deque. */
    int getRear() {
        if(isEmpty())
            return -1;
        return myque.back();
    }

    /** Checks whether the circular deque is empty or not. */
    bool isEmpty() {
        return myque.size() == 0;
    }

    /** Checks whether the circular deque is full or not. */
    bool isFull() {
        return myque.size() == size;
    }
private:
    vector<int> myque;
    int size;
};

/**
 * Your MyCircularDeque object will be instantiated and called as such:
 * MyCircularDeque obj = new MyCircularDeque(k);
 * bool param_1 = obj.insertFront(value);
 * bool param_2 = obj.insertLast(value);
 * bool param_3 = obj.deleteFront();
 * bool param_4 = obj.deleteLast();
 * int param_5 = obj.getFront();
 * int param_6 = obj.getRear();
 * bool param_7 = obj.isEmpty();
 * bool param_8 = obj.isFull();
 */