체육복

체육복

2020.07.26

const initHash = (num) => {
  const hash = {};
  for (let i = 1; i <= num; i++) {
    hash[i] = 1;
  }
  return hash;
};

const solution = (n, lost, reserve) => {
  const hashTable = initHash(n);

  lost.forEach((num) => {
    hashTable[num]--;
  });

  reserve.forEach((num) => {
    hashTable[num]++;
  });

  const whoNeedsHelp = Object.entries(hashTable)
    .filter(([key, value]) => value == 0)
    .map(([key, value]) => parseInt(key));

  whoNeedsHelp.forEach((num) => {
    if (hashTable[num - 1] == 2) {
      hashTable[num - 1]--;
      hashTable[num]++;
    } else if (hashTable[num + 1] == 2) {
      hashTable[num + 1]--;
      hashTable[num]++;
    }
  });

  const filteredResult = Object.values(hashTable).filter((value) => value);

  return filteredResult.length;
};

• 탐욕법이 뭘까...

• 딱히 코멘트할 것이 없는 것 같다

2020.09.12

function solution(n, lost, reserve) {
  const list = new Array(n).fill(1);
  lost.forEach((nth) => {
    list[nth - 1]--;
  });
  reserve.forEach((nth) => {
    list[nth - 1]++;
  });
  for (let i = 0; i < n; i++) {
    if (list[i] == 0) {
      if (list[i - 1] == 2) {
        list[i - 1]--;
        list[i]++;
        continue;
      }
      if (list[i + 1] == 2) {
        list[i + 1]--;
        list[i]++;
        continue;
      }
    }
  }
  return list.filter((num) => num > 0).length;
}

• 여전히 탐욕법이 뭔지는...