yukicoder No.40 多項式の割り算

YukiCoder60.nb

(* http://yukicoder.me/problems/no/40 *)

cl[li_] := 
 CoefficientList[PolynomialRemainder[FromDigits[Reverse[li], x], x^3 - x, x], x]
 
ans[{}] := {0}
ans[li_] := li
 
In[1]:= ans[f[{1, 1, 1, 0, 0, 1}]]
Out[1]= {1, 2, 1}
 
In[2]:= ans[cl[{0, -5 , 0, 4, 0, 1, -1, 0, 1}]]
Out[2]= {0}
 
In[3]:= ans[cl[{-5, 0, -1, 1, 1, 1}]]
Out[3]= {-5, 2}