30秒学会 Dart 片段 – mostFrequent

Returns the most frequent element in a list.

Use Iterable.toSet() to get the unique values of the list, Set.reduce() to iterate over them and Iterable.where() to find the most frequent element.

代码实现

T mostFrequent<T>(Iterable<T> itr) {
  return itr.toSet().reduce((i, j) =>
    itr.where((v) => v == i).length > itr.where((v) => v == j).length ? i : j);
}

使用样例

mostFrequent(['a', 'b', 'a', 'c', 'a', 'a', 'b']); // 'a'