ARTS 日常打卡 - 7

class MyCircularDeque {public:    /** Initialize your data structure here. Set the size of the deque to be k. */    vector<int> arr;    int cnt, head, tail; //当钱队列元素数量 头指针 尾指针    MyCircularDeque(int k): arr(k), head(0), tail(0), cnt(0) {}        /** Adds an item at the front of Deque. Return true if the operation is successful. */    bool insertFront(int value) {        if (isFull()) return false;        head = head - 1;        if (head == -1) head = arr.size() - 1;        arr[head] = value;        cnt += 1;        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;        arr[tail] = value;        tail +=1;        if(tail == arr.size()) tail = 0;        cnt += 1;        return true;     }        /** Deletes an item from the front of Deque. Return true if the operation is successful. */    bool deleteFront() {        if(isEmpty()) return false;
        head = (head+1) % arr.size();        cnt -= 1;
        return true;    }        /** Deletes an item from the rear of Deque. Return true if the operation is successful. */    bool deleteLast() {        if(isEmpty()) return false;
        tail = (tail -1 + arr.size()) % arr.size();            cnt -= 1;
        return true;    }        /** Get the front item from the deque. */    int getFront() {        if(isEmpty()) return -1;
        return arr[head];    }        /** Get the last item from the deque. */    int getRear() {        if(isEmpty()) return -1;        return arr[(tail - 1 + arr.size()) % arr.size()];    }        /** Checks whether the circular deque is empty or not. */    bool isEmpty() {        return cnt == 0;    }        /** Checks whether the circular deque is full or not. */    bool isFull() {        return arr.size() == cnt;    }};
/** * 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(); */