从数组中删除非唯一行

function removeNonUniqueRows(arr) {
  const hashTable = {};
  
  // 遍历数组，构建哈希表
  for (let i = 0; i < arr.length; i++) {
    const row = arr[i].toString();
    if (hashTable[row]) {
      hashTable[row]++;
    } else {
      hashTable[row] = 1;
    }
  }
  
  const result = [];
  
  // 再次遍历数组，根据哈希表判断是否保留行
  for (let i = 0; i < arr.length; i++) {
    const row = arr[i].toString();
    if (hashTable[row] === 1) {
      result.push(arr[i]);
    }
  }
  
  return result;
}

// 示例用法
const array = [[1, 2, 3], [4, 5, 6], [1, 2, 3], [7, 8, 9]];
const uniqueRows = removeNonUniqueRows(array);
console.log(uniqueRows);