polynomial roots

(*Mathematica start*)
nn = 10
a = Table[1, {n, 1, nn}];
nn = Length[a];
b = Flatten[
   Table[Permutations[
     Table[Table[If[n >= k, a[[n - k + 1]], 0], {k, 1, nn}], {n, 0,
        nn}][[i]]], {i, 1, nn + 1}], 1];
data = Flatten[
   Table[x /.
     N[Solve[Total[Transpose[Transpose[b]*x^(Range[nn] - 1)][[i]]] ==
        0, x]], {i, 1, Length[b]}]];
p = ListPlot[{Re[#], Im[#]} & /@ data, AxesOrigin -> {0, 0},
   PlotRange -> {{-2, 2}, {-2, 2}}, ImagePadding -> 40,
   AspectRatio -> 1, Frame -> True,
   FrameLabel -> {{Im, None}, {Re, "complex plane"}},
   PlotStyle -> Directive[Blue, PointSize[.013]]];
Show[p, Graphics@Circle[{0, 0}, 1]]
(*Mathematica end*)