2959c81e_ufficient_Mating_Material_Rule__2
[0] Example I [2] 
White to move. This setup is also drawn immediately according to the rule after black's move. It was Ra8+. White can't move anything else, but capture the black rook by Kxa8. After Kxa8 the setup would be drawn. So, in this position it's impossible to avoid the drawn position. Therefore there is no way to end the game in either side's mate. Therefore the game is drawn right after black's Ra8+.
[E4EC] The insufficient Mating Material Rule
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