优先级队列(基于数组)

class Queue {
    constructor() {
        this.list = []
    }
    push(value) {
        this.list.push(value)
    }
    pop() {
        return this.list.shift()
    }
    peek() {
        return this.list[0]
    }
    isEmpty() {
        return this.list.length === 0
    }
    clear() {
        this.list = []
    }
    size() {
        return this.list.length
    }
    toString() {
        return this.list.join(",")
    }
}

// 优先级队列
class PriorityQueue extends Queue {
    push(value, priority = 0) {
        let insertIndex = this.list.length;
        for (let i = 0; i < this.list.length; i++) {
            if (priority <= this.list[i][1]) {
                insertIndex = i;
                break;
            }
        }
        this.list.splice(insertIndex, 0, [value, priority])
    }
    pop() {
        let item = this.list.shift();
        return item ? item[0] : undefined;
    }
    peek() {
        let item = this.list[0];
        return item ? item[0] : undefined;
    }
    toString() {
        let resArr = [];
        this.list.forEach((item) => {
            resArr.push(item[0])
        })
        return resArr.join(",")
    }
}


// 测试代码
const queue = new PriorityQueue();
queue.push("C", 3)
queue.push("B", 2)
queue.push("A", 1)
queue.push("BB", 2)
queue.pop();
queue.push("D", 5)
console.log(queue.toString())
console.log(queue.peek())
console.log(queue.size())
console.log(queue.isEmpty())
queue.clear();
console.log(queue.pop())
console.log(queue.peek())
console.log(queue.toString())
console.log(queue.isEmpty())