Damm(num){
	row := 1, Damm := [[0,3,1,7,5,9,8,6,4,2]
			  ,[7,0,9,2,1,5,4,8,6,3]
			  ,[4,2,0,6,8,7,1,3,5,9]
			  ,[1,7,5,0,9,8,3,4,2,6]
			  ,[6,1,2,3,0,4,5,9,7,8]
			  ,[3,6,7,4,2,0,9,5,8,1]
			  ,[5,8,6,9,7,2,0,1,3,4]
			  ,[8,9,4,5,3,6,2,0,1,7]
			  ,[9,4,3,8,6,1,7,2,0,5]
			  ,[2,5,8,1,4,3,6,7,9,0]]
	for i, v in StrSplit(SubStr(num, 1, -1)){
		++row := Damm[row, v+1]
	}
	return (SubStr(num, 0)=row-1 && !Damm[row, row])
}