2的一百次方减2的99次方减2的98次方减省略号减2的2次方减2减1
=2^100-2^99-……-2^2-2-1
=2^99*(2-1)-2^98-……-2^2-2-1
=2^99-2^98-……-2^2-2-1
=2^2-2-1
=1