20172017*2017-20172016*2016-20172016
=20172017*2017-20172016*(2016+1)
=20172017*2017-20172016*2017
=2017*(20172017-20172016)
=2017*1
=2017
2017
20172017×2017-20172016×2016-20172016
=(20172016+1)×(2016+1)-20172016×2016-20172016
=20172016×2016+20172016+2016+1-20172016×2016-20172016
=2016+2016+1
=4033
………… ======2017=0
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