Preferred Alternative
class class(es)
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0 none = class 0
0 = not valid
1 = not valid
2 = not valid
3 = not valid
4 = not valid
1 none = class 1 or 0
0 = class 1 or 0
1 = class 1 or 0
2 = not valid
3 = not valid
4 = not valid
2 none = class 2
0 = class 2 or 0
1 = not valid
2 = class 2
2 = class 2
3 = not valid
4 = not valid
3 none = class 3 or 2
0 = class 3, 2 or 0
1 = class 3, 2, 1 or 0
2 = class 3 or 2
3 = class 3 or 2
4 = not valid
4 none = class 4 or 2
0 = class 4, 2 or 0
1 = class 4, 2, 1 or 0
2 = class 4 or 2
3 = class 4, 3, or 2
4 = class 4 or 2