Перемножение многочленов

 program spisky;
 
 type 
  TMng = record
    n: integer;
    a: array [1...100] of Real;
    s: array [1...100] of Integer;
end;
 
Var
   m1, m2, m3: TMng;
   i, j: Integer;
   st: string;
 
function TMngToStr (m1: TMng): string;

const
  a: array[0..4] of Integer = (1,0,-4,0,2); //2x^4-4x^2+1 
  b: array[0..4] of Integer = (0,-2,0,1,0);

function Multi(a, b : array of Integer) : array of Integer;
begin
  SetLength(Result, a.Length + b.Length);
  for var i := 0 to Result.Length-1 do Result[i] := 0;
  
  for var i := 0 to a.Length-1 do
    for var j := 0 to b.Length-1 do
      Result[i + j] += a[i] * b[j];
end;
 
function MnToStr(c : array of Integer) : String;
begin
  var xi : String;
  for var i := c.Length-1 downto 0 do
    begin
      case i of
        0 : xi := '';
        1 : xi := 'x';
      else  xi := 'x^' + i;
      end; 
    
      case sign(c[i]) of
        -1 : if Result.Length = 0 then Result := c[i] + xi else Result += ' - ' + abs(c[i]) + xi;
        +1 : if Result.Length = 0 then Result := c[i] + xi else Result += ' + ' + c[i] + xi;
      end;
    end;
end;
 
begin
  // (x-2) * (3x+1) * (4x-3) = 12x^3 - 29x^2 + 7x + 6
  WriteLn(MnToStr(Multi(Multi(arr(-2,1), arr(1,3)), arr(-3,4))));
 
  var a := arr(1,0,-4,0,2);
  var b := arr(0,-2,0,1,0);
  WriteLn(MnToStr(Multi(a,b)));
end.