77+123×24=77+(123×24+123)-123.24与25接近,就构造25吧=77-123+(123×24+123)=-46+123×25.(一般构造的时候都会考虑25与4相乘,125与8相乘)=-46+(123×25+25)-25=-46-25+124×25=-71+31×4×25=-71+31×(4×25)=-71...