rt

deleted

Edited by author 21.10.2017 21:07

Why not std:: complex?
I have not read the code very carefully, maybe miss something important

Maybe not possible to made it long double?

it involves with Chebyshev polynomial  U(x) is Chebyshev polynomial

Um(i*An/2)= i*An*Um-1(i*An/2)-Um-2(i*An/2)   i is unit imaginary number

An is a n*n matrix  Aij==1 if and only if abs(i-j)==1.

sqrt(det(Um(i*An/2）) is the answer..

I use long double because I need to judge the sign of sqrt(ans^2)

Edited by author 21.10.2017 09:46

Delete the code please. Posting AC code here violates the rules. You can explain your idea (which is not recommended either)

100 100
exactly result:
211296849512315762188619578574048657110653043609449472144725843973442479614058285996396387014570402447830177110492225916018306620473309898122553032154580078102848452707439935767561964432764309438889871659414420572001206784720890894593722611533746574726650832697664485530063095995962974740556608440361525520881534009295321784945692404915331234788462418215336479515406547891566477310928856298254153861327506039317299734093964771367687300616477954739907701770903890588939771176356807995358624375906635501695115399580918628783125903772434369374398388373031207325810190683145008704318854255120274024753774893652675256050843161415941752800234892558301824773136514256893938068687029095739098286424428752900415743287209790876036884080292271611832363684077924978489349099638343563775430445274281910983984807471952213028600596500243377496299053827784481766322799764412944529657092342282080566012889979741375614523723377108743228485047911163027695369684514018557778209543315449702696764786683247792132799136211383970764610828007749277178715661259454260357449248458683734007683846942145977953891807183259007702385978401831386444472112720952063414073905105738447216839800171442748174691808886777635485410113868685679678838952355104065272999262338505349001538065924096