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Dart: Scalable Application Development by Ivo Balbaert, Sergey Akopkokhyants, Davy Mitchell

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Generating a random number within a range

You may have often wondered how to generate a random number from within a certain range. This is exactly what we will look at in this recipe; we will obtain a random number that resides in an interval between a minimum (min) and maximum (max) value.

How to do it...

This is simple; look at how it is done in random_range.dart:

import 'dart:math';

var now = new DateTime.now();
Random rnd = new Random();
Random rnd2 = new Random(now.millisecondsSinceEpoch);

void main() {
  int min = 13, max = 42;
  int r = min + rnd.nextInt(max - min);
  print("$r is in the range of $min and $max"); // e.g. 31
  // used as a function nextInter:
  print("${nextInter(min, max)}"); // for example: 17

 int r2 = min + rnd2.nextInt(max - min); ...

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