백준 10845 큐 (자료구조)

문제

제한 사항

입출력 예

풀이

class Queue {
  constructor() {
    this.arr = [];
  }
  size() {
    return this.arr.length;
  }
  enqueue(item) {
    this.arr.push(item);
  }
  dequeue() {
    if (!this.arr.length) {
      return -1;
    } else {
      const result = this.arr.shift();
      return result;
    }
  }
  front() {
    if (!this.arr.length) {
      return -1;
    } else {
      return this.arr[0];
    }
  }
  back() {
    if (!this.arr.length) {
      return -1;
    } else {
      return this.arr[this.arr.length - 1];
    }
  }
  isEmpty() {
    if (!this.arr.length) {
      return 1;
    } else {
      return 0;
    }
  }
}
const input = require('fs').readFileSync('/dev/stdin').toString().trim().split('\n');
const N = +input.shift();
const myQueue = new Queue();
let answer = "";
input.forEach((e, i) => {
  const [cmd, item] = e.split(" ");
  if (cmd === "push") {
    myQueue.enqueue(item);
  } else if (cmd === "front") {
    answer += myQueue.front() + "\n";
  } else if (cmd === "size") {
    answer += myQueue.size() + "\n";
  } else if (cmd === "pop") {
    answer += myQueue.dequeue() + "\n";
  } else if (cmd === "back") {
    answer += myQueue.back() + "\n";
  } else {
    if (myQueue.isEmpty()) {
      answer += 1 + "\n";
    } else {
      answer += 0 + "\n";
    }
  }
});

console.log(answer.trim());

• class로 큐 자료구조를 구현하여 풀었다.