var
  f1,f2:text;
  min2,min1,w1,h1:int64;
n: int64;
 w,h,sq:int64;
  x1,y1,mid:int64;
procedure bin (minn,maxx:int64);
begin
  if (abs(maxx-minn)=0) then
begin
    min2:=minn;
    exit;
  end;
    mid:=(minn+maxx) div 2;

      if ((mid div w) * (mid div h)>=n) then
       bin(minn,mid)
      else
       bin(mid + 1,maxx);


end;

begin
  assign(f1,'diploma.in');
  assign(f2,'diploma.out');
  reset(f1);
  rewrite(f2);
  read(f1,w);
  read(f1,h);
  read(f1,n);

  bin(1,w * n);


write(f2,min2);
close(f1);
close(f2);

end.