//Convert a Decimal Number to Any Other Representation

//https://en.wikipedia.org/wiki/Positional_notation#Base_conversion

import 'package:test/expect.dart';

import 'package:test/scaffolding.dart';

String decimalToAny(int value, int base) {

var ALPHABET_VALUES = {

10: 'A',

11: 'B',

12: 'C',

13: 'D',

14: 'E',

15: 'F',

16: 'G',

17: 'H',

18: 'I',

19: 'J',

20: 'K',

21: 'L',

22: 'M',

23: 'N',

24: 'O',

25: 'P',

26: 'Q',

27: 'R',

28: 'S',

29: 'T',

30: 'U',

31: 'V',

32: 'W',

33: 'X',

34: 'Y',

35: 'Z',

};

if (value == 0) return "0";

if (base < 2 || base > 36) throw FormatException("Base not supported!");

bool negative = false;

if (value < 0) {

negative = true;

value *= -1;

}

String output = "";

while (value > 0) {

int remainder = value % base;

value = value ~/ base;

output =

(remainder < 10

? remainder.toString()

: ALPHABET_VALUES[remainder] ?? '0') +

output;

}

return negative ? '-' + output : output;

}

void main() {

test('test case 1', () => expect(decimalToAny(0, 2), '0'));

test('test case 2', () => expect(decimalToAny(5, 4), '11'));

test('test case 3', () => expect(decimalToAny(20, 3), '202'));

test('test case 4', () => expect(decimalToAny(-58, 16), '-3A'));

test('test case 5', () => expect(decimalToAny(243, 17), 'E5'));

test('test case 6', () => expect(decimalToAny(34923, 36), 'QY3'));

test('test case 7', () => expect(decimalToAny(10, 11), 'A'));

test('test case 8', () => expect(decimalToAny(-16, 16), '-10'));

test('test case 9', () => expect(decimalToAny(36, 36), '10'));

}