1.2345+2.3451+3.4512+4.5123+5.1234
=1+2+3+4+5+0.1+0.2+0.3+0.4+0.5++0.01+0.02+0.03+0.04+0.05+0.001+0.002+0.003+0.004+0.005+0.0001+0.0002+0.0003+0.0004+0.0005
=10+1+0.1+0.01+0.001
=11.111