백준 단계별 - 정렬

1. 2750번 - 수 정렬하기

삽입 정렬과 거품 정렬을 이용해서 풀었음

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

// 삽입 정렬
const insertionSort = array => {
  for (let i = 1; i < array.length; i++) {
    let prev = i - 1;
    let current = array[i];

    while (prev >= 0 && current < array[prev]) {
      array[prev + 1] = array[prev];
      prev--;
    }

    array[prev + 1] = current;
  }

  return array;
};
// 거품 정렬
const bubbleSort = array => {
  for (let i = 0; i < array.length; i++) {
    for (let j = 1; j < array.length - i; j++) {
      if (array[j] < array[j - 1]) {
        const temp = array[j];
        array[j] = array[j - 1];
        array[j - 1] = temp;
      }
    }
  }

  return array;
};

const input = [];

rl.on("line", line => {
  input.push(+line);

  if (input.length >= 2 && input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  //정답 기록
  let answer = "";

  bubbleSort(input).forEach(v => (answer += `${v}\n`));

  console.log(answer);

  process.exit();
});

2. [2751번 - 수 정렬하기 2](https://www.acmicpc.net/problem/2751

삽입 정렬, 퀵 정렬, 힙 정렬로 풀어봤는데 각각 메모리 초과, 시간 초과, 런타임 에러(stackSizeExceedd)에러가 나서 JS의 내장함수인 array.prototype.sort()를 이용해서 풀었음

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(+line);

  if (input.length >= 2 && input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  const array = input;

  //정답 기록
  let answer = "";

  array.sort((x, y) => (x === y ? 0 : x > y ? 1 : -1));

  array.forEach(v => (answer += `${v}\n`));

  console.log(answer);

  process.exit();
});

3. [10989번 - 수 정렬하기 3](https://www.acmicpc.net/problem/10989

카운팅 정렬을 사용했으나 메모리 초과 발생

/**
 * 카운팅 정렬 사용
 */
const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(+line);

  if (input.length >= 2 && input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  //정답 기록
  let answer = "";

  const maxNumber = Math.max(...input);
  const array = Array(maxNumber).fill(0);

  input.forEach(v => array[v - 1]++);

  array.forEach((v, index) => {
    for (let i = 0; i < v; i++) {
      answer += `${index + 1}\n`;
    }
  });

  console.log(answer);

  process.exit();
});

4. 2108번 - 통계학

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(+line);

  if (input.length >= 2 && input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();
  const array = input;

  array.sort((x, y) => (x === y ? 0 : x > y ? 1 : -1));

  // 음수값도 존재하기 때문에 객체에다가 넣음 ( 프로퍼티키: 입력숫자, 프로퍼티밸류: 반복수 )
  const obj = {};
  array.forEach(v => {
    if (obj[v]) {
      obj[v]++;
    } else {
      obj[v] = 1;
    }
  });

  let maximumRepeat = 0;
  const tempArray = [];

  // 반복수가 제일 많은 반복수를 찾음
  for (let p in obj) {
    if (obj[p] > maximumRepeat) {
      maximumRepeat = obj[p];
    }
  }
  // 반복수가 제일 많은 놈들을 tempArray에 넣음
  for (let p in obj) {
    if (obj[p] === maximumRepeat) {
      tempArray.push(+p);
    }
  }
  // 오름차순 정렬
  tempArray.sort((x, y) => (x > y ? 1 : -1));

  let mean = Math.round(array.reduce((prev, curr) => prev + curr) / array.length);
  let median = array[Math.floor(array.length / 2)];
  let mode = tempArray.length >= 2 ? tempArray[1] : tempArray[0];
  let range = array[array.length - 1] - array[0];

  let answer = "";

  answer = `${mean}\n${median}\n${mode}\n${range}\n`;

  console.log(answer);

  process.exit();
});

5. 1427번 - 소트인사이드

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  rl.close();
}).on("close", () => {
  const numberArray = input.shift().split("");

  numberArray.sort((x, y) => (x === y ? 0 : x < y ? 1 : -1));

  let answer = numberArray.join("");

  console.log(answer);

  process.exit();
});

6. 11650번 - 좌표 정렬하기

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  if (input.length >= 2 && +input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  const array = input.map(v => v.split(" ").map(v => +v));

  array.sort((x, y) => {
    if (x[0] === y[0]) {
      if (x[1] > y[1]) return 1;
      else return -1;
    } else if (x[0] > y[0]) {
      return 1;
    } else {
      return -1;
    }
  });

  let answer = "";

  array.forEach(v => (answer += `${v.join(" ")}\n`));

  console.log(answer);

  process.exit();
});

7. 11651번 - 좌표 정렬하기 2

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  if (input.length >= 2 && +input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  const array = input.map(v => v.split(" ").map(v => +v));

  array.sort((x, y) => {
    if (x[1] === y[1]) {
      if (x[0] > y[0]) return 1;
      else return -1;
    } else if (x[1] > y[1]) {
      return 1;
    } else {
      return -1;
    }
  });

  let answer = "";

  array.forEach(v => (answer += `${v.join(" ")}\n`));

  console.log(answer);

  process.exit();
});

8. 1181번 - 단어 정렬

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  if (input.length >= 2 && +input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  // 중복제거
  const array = [...new Set(input)];

  const tempArray = [];

  array.forEach(v => {
    if (tempArray[v.length] === undefined) tempArray[v.length] = [];

    tempArray[v.length].push(v);
  });

  let answer = "";

  tempArray.forEach(value => {
    if (value.length === 1) return (answer += `${value[0]}\n`);

    value.sort((x, y) => (x > y ? 1 : -1));

    value.forEach(v => (answer += `${v}\n`));
  });

  console.log(answer);

  process.exit();
});

9. 10814번 - 나이순 정렬

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  if (input.length >= 2 && +input[0] === input.length - 1) rl.close();
}).on("close", () => {
  input.shift();

  const array = input.map((v, i) => {
    const tempArray = v.split(" ").map((v, i) => (i === 0 ? +v : v));
    tempArray.push(i);
    return tempArray;
  });

  array.sort((x, y) => {
    if (x[0] === y[0]) {
      return x[2] > y[2] ? 1 : -1;
    } else {
      return x[0] > y[0] ? 1 : -1;
    }
  });

  let answer = "";

  array.forEach(v => (answer += `${v[0]} ${v[1]}\n`));

  console.log(answer);

  process.exit();
});

10. 18870번 - 좌표 압축

const readline = require("readline");
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const input = [];

rl.on("line", line => {
  input.push(line);

  if (input.length >= 2 && +input[0] === input[1].split(" ").length) rl.close();
}).on("close", () => {
  input.shift();

  // 문자열 => 배열 => 숫자배열 => 중복제거
  const array = [...new Set(input[0].split(" ").map(v => +v))];

  array.sort((x, y) => (x > y ? 1 : -1));
  const table = {};
  array.forEach((v, i) => (table[v] = i));

  let answer = "";

  input[0].split(" ").forEach(v => (answer += `${table[v]} `));
  console.log(answer);

  process.exit();
});