浮動小数点数

Microsoft Office Excel

=+0.1+0.4-0.5 = 0
=+0.1-0.5+0.4 = 0
=+0.4+0.1-0.5 = 0
=+0.4-0.5+0.1 = 0
=-0.5+0.4+0.1 = 0
=-0.5+0.1+0.4 = 0
=(+0.1+0.4-0.5) = 0
=(+0.1-0.5+0.4) = 0
=(+0.4+0.1-0.5) = 0
=(+0.4-0.5+0.1) = 2.78E-17(=1/2^55)
=(-0.5+0.4+0.1) = 2.78E-17(=1/2^55)
=(-0.5+0.1+0.4) = 0