a,53743.136,61003.826
b,47943.002,66225.854
c,40049.229,53782.790
d,36924.728,61027.086
******************
1,48580.2674,60500.5005
2,48681.3806,55018.2883
3,43767.1890,57968.6068
4,40843.3222,64867.9795
*******************
1,b
1,a
2,a
1,2
2,3
2,c
c,3
d,3
3,4
1,3
d,4
1,4
b,4