How to Rotate Elements in a List in Dart - Step by Step Examples

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How to Rotate Elements in a List in Dart ?

Answer

To rotate elements in a list in Dart, you can use the `rotate` method provided by the `dart:core` library.

✐ Examples

1 Rotate Elements in a List of Integers

In this example,

We create a list named numbers with integer values.
We use the rotate method to rotate the elements by a specified distance.
Finally, we print the rotated list to standard output.

Dart Program

void main() {
  List<int> numbers = [1, 2, 3, 4, 5];
  int distance = 2;
  numbers.rotate(distance);
  print('Rotated list: \$numbers');
}

extension ListExtension<T> on List<T> {
  void rotate(int distance) {
    if (distance > 0) {
      addAll(getRange(0, distance));
      removeRange(0, distance);
    } else if (distance < 0) {
      insertAll(0, getRange(length + distance, length));
      removeRange(length + distance, length);
    }
  }
}

Output

Rotated list: [4, 5, 1, 2, 3]

2 Rotate Elements in a List of Strings

In this example,

We create a list named words with string values.
We use the rotate method to rotate the elements by a specified distance.
Finally, we print the rotated list to standard output.

Dart Program

void main() {
  List<String> words = ['apple', 'banana', 'cherry', 'date', 'elderberry'];
  int distance = 3;
  words.rotate(distance);
  print('Rotated list: \$words');
}

extension ListExtension<T> on List<T> {
  void rotate(int distance) {
    if (distance > 0) {
      addAll(getRange(0, distance));
      removeRange(0, distance);
    } else if (distance < 0) {
      insertAll(0, getRange(length + distance, length));
      removeRange(length + distance, length);
    }
  }
}

Output

Rotated list: [date, elderberry, apple, banana, cherry]

Summary

In this tutorial, we learned How to Rotate Elements in a List in Dart language with well detailed examples.

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How to Rotate Elements in a List in Dart - Step by Step Examples

How to Rotate Elements in a List in Dart ?

Answer

✐ Examples

1 Rotate Elements in a List of Integers

Dart Program

Output

2 Rotate Elements in a List of Strings

Dart Program

Output

Summary

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