procedure POLCOF(XA, YA:array of real; N:integer; var COF:array of real);
var
    X, Y:array[0..15] of real;
    I,J,K:integer;
    XMIN,DY:real;
begin
    For J:=1 To N do
    begin
        X[J]:=XA[J];
        Y[J]:=YA[J];
    end;
    For J:=1 To N do
    begin
        POLINT(X, Y, N + 1 - J, 0, COF[J], DY);
        XMIN:=1E+38;
        K:=0;
        For I:=1 To N + 1 - J do
        begin
            If Abs(X[I]) < XMIN Then
            begin
                XMIN:=Abs(X[I]);
                K:=I;
            end;
            If X[I] <> 0 Then Y[I]:=(Y[I] - COF[J]) / X[I];
        end;
        If K < N + 1 - J Then
        begin
            For I:=K + 1 To N + 1 - J do
            begin
                Y[I - 1]:=Y[I];
                X[I - 1]:=X[I];
            end;
        end;
    end;
end;