[16번][중급] 두개 뽑아서 더하기

문제

https://programmers.co.kr/learn/courses/30/lessons/68644

프로그래머스

 

나의 답

[pseudo code]
1. pointer=0
2. 배열을 돌면서 (i=pointer+1 부터) 더한 값을 answer 배열에 push
3. 이때, 더한 값이 answer 배열에 있는지 확인 한 후 없으면 push
4. sort해줌

 

=> Set을 사용하면 자동으로 중복 값 없이 배열을 반환해 훨씬 간단함

function solution(numbers) {
  const answer = [];
  function sum(pointer) {
    for (let i = pointer + 1; i < numbers.length; i++) {
      const sum = numbers[pointer] + numbers[i];
      if (!answer.includes(sum)) {
        answer.push(sum);
      }
    }
    console.log(pointer, answer);
    pointer++;
    return pointer == numbers.length - 1
      ? answer.sort((a, b) => a - b)
      : sum(pointer);
  }
  sum(0);
  return answer;
}

console.log(solution([2, 1, 3, 4, 1]));


// Set 사용!!
function solution(numbers) {
  const temp = [];
  let answer = [];
  function sum(pointer) {
    for (let i = pointer + 1; i < numbers.length; i++) {
      temp.push(numbers[pointer] + numbers[i]);
    }
    pointer++;
    return pointer == numbers.length - 1
      ? (answer = [...new Set(temp)].sort((a, b) => a - b))
      : sum(pointer);
  }
  sum(0);
  return answer;
}