31671660 = X1*1106 + X2*2506 + X3*6745 + X4*8145 一 8220 = X1 + X2 + X3 + X4 二 22580340 = 0 + X2*1400 + X3*5639 + X4*7039 三 11072340 = - X1*1400 + 0 + X3*4239 + X4*5639 四