原式=481+265+904-184-160-703+1/2x3+1/3x4+1/4x5-1/5x6-1/6x7-1/7x8=603+1/2-1/3+1/3-1/4+1/4-1/5+1/6-1/5/+1/7-1/6+1/8-1/7=603+1/2-2/5+1/8=603+9/40=603又9/40
把分数和整数拆开算
