"解原式=1/2-1/2+1/3-1/3+1/4+…1/99+1/100=1/100补充：=（1/2-1/2)+(1/3-1/3)+(1/4-1/4)+…+(1/99-1/99)+1/100
=0+0+0+…+0+1/100=1/100