回复 1# isee
就用辗转相除法吧,像下面这样:
243,551
243,551=243*2+65
243,65
243=65*3+48,65
48,65
48,65=48+17
48,17
48=17*2+14,17
14,17
14,17=14+3
14,3
14=3*4+2,3
2,3
2,3=2+1
2,1
然后倒推回去,上面最后一步是用2除3,商1余1
1=3-2*1=3-(14-3*4)=(17-14)-(14-(17-14)*4)
=(17-(48-17*2))-((48-17*2)-(17-(48-17*2))*4)
=((65-48)-(48-(65-48)*2))-((48-(65-48)*2)-((65-48)-(48-(65-48)*2))*4)
=((65-(243-65*3))-((243-65*3)-(65-(243-65*3))*2))-(((243-65*3)-(65-(243-65*3))*2)-((65-(243-65*3))-((243-65*3)-(65-(243-65*3))*2))*4)
=(((551-243*2)-(243-(551-243*2)*3))-((243-(551-243*2)*3)-((551-243*2)-(243-(551-243*2)*3))*2))-(((243-(551-243*2)*3)-((551-243*2)-(243-(551-243*2)*3))*2)-(((551-243*2)-(243-(551-243*2)*3))-((243-(551-243*2)*3)-((551-243*2)-(243-(551-243*2)*3))*2))*4)
=(((x-y*2)-(y-(x-y*2)*3))-((y-(x-y*2)*3)-((x-y*2)-(y-(x-y*2)*3))*2))-(((y-(x-y*2)*3)-((x-y*2)-(y-(x-y*2)*3))*2)-(((x-y*2)-(y-(x-y*2)*3))-((y-(x-y*2)*3)-((x-y*2)-(y-(x-y*2)*3))*2))*4)
=86x-195y
其中x代表551,y代表243 |