decode method
Implementation
List<int> decode(List<int> packed) {
final out = <int>[];
for (var i = 0; i + 1 < packed.length; i += 2) {
final v = packed[i];
final c = packed[i + 1];
for (var j = 0; j < c; j++) {
out.add(v);
}
}
return out;
}