javascript -如何删除数组中的所有单个条目

function removeSingleEntries(arr) {
  const counts = {};
  arr.forEach(item => {
    counts[item] = (counts[item] || 0) + 1;
  });

  return arr.filter(item => counts[item] > 1);
}

// 示例
const array = [1, 2, 3, 2, 4, 5, 5, 6];
const result = removeSingleEntries(array);
console.log(result); // 输出: [2, 2, 5, 5]

function removeSingleEntries(arr) {
  const counts = new Map();
  arr.forEach(item => {
    counts.set(item, (counts.get(item) || 0) + 1);
  });

  return arr.filter(item => counts.get(item) > 1);
}

// 示例
const array = [1, 2, 3, 2, 4, 5, 5, 6];
const result = removeSingleEntries(array);
console.log(result); // 输出: [2, 2, 5, 5]