flying-flash-9887

readme.md

Create 1D Random Dice

use dart:math to create a random number and fill it inside the dice(list).

Set Specific Rules for dice

  /// set dice position
  ///  (0,0)  [(0,1)]  (0,2)   (0,3)
  /// [(1,0)] [(1,1)] [(1,2)] [(1,3)]
  ///  (2,0)  [(2,1)]  (2,2)   (2,3)

  /// <pos> > <index>
  /// (0,1) > 0
  /// (1,0) > 1
  /// (1,1) > 2
  /// (1,2) > 3
  /// (1,3) > 4
  /// (2,1) > 5

  /// set pair <pos> : <index>
  /// (0,1) - (2,1) : 0 - 5
  /// (1,0) - (1,2) : 1 - 3
  /// (1,1) - (1,3) : 2 - 4

Practice Dart

• use user-defined function
• use while and for loop
• use switch-case
• use if-else
• use ternary ( ? : )
• use final and late
• use List.filled constructor
• use library (dart:math)

main.dart

import 'dart:math';

void main() {
  /// init 1d array
  List<int> dice1D = List.filled(6, 0);

  /// set dice position
  ///  (0,0)  [(0,1)]  (0,2)   (0,3)
  /// [(1,0)] [(1,1)] [(1,2)] [(1,3)]
  ///  (2,0)  [(2,1)]  (2,2)   (2,3)

  /// <pos> > <index>
  /// (0,1) > 0
  /// (1,0) > 1
  /// (1,1) > 2
  /// (1,2) > 3
  /// (1,3) > 4
  /// (2,1) > 5

  /// set pair <pos> : <index>
  /// (0,1) - (2,1) : 0 - 5
  /// (1,0) - (1,2) : 1 - 3
  /// (1,1) - (1,3) : 2 - 4

  /// set rules
  bool hasDiceFormat(List<int> dice) {
    if (dice.length != 6) return false;
    return (dice[0] + dice[5]) == 7 &&
        (dice[1] + dice[3]) == 7 &&
        (dice[2] + dice[4]) == 7;
  }

  for (int i = 0; i < 3; i++) {
    /// set random number
    int randomNumber = -1;
    
    while(true) {
      final int n = Random().nextInt(6) + 1;
      
      bool isUnique = true;
      for(int j = 0; j < 6; j++) {
        if(dice1D[j] == n) {isUnique = false; break;}
      }
      
      if(isUnique) {
        randomNumber = n;
        break;
      }
    }
    
    if(randomNumber == -1) return;
 

    if (dice1D[i] == 0) {
      dice1D[i] = randomNumber;

      late int oppositeIndex;
      switch (i) {
        case 0:
          oppositeIndex = 5;
          break;
        case 1:
          oppositeIndex = 3;
          break;
        case 2:
          oppositeIndex = 4;
          break;
        default:
          oppositeIndex = -1;

          break;
      }

      if (oppositeIndex != -1) {
        dice1D[oppositeIndex] = 7 - randomNumber;
      }
    }
  }
  
  /// check if the dice is made properly
  print('The dice has made ${hasDiceFormat(dice1D) ? 'perfectly' : 'bad'} -> $dice1D');
}