program cowties(input,output);
type
 point=record
  x,y:integer;
end;
var
 map:array[-100..100,-100..100]of boolean;
 a:array[1..100,1..40]of point;
 s:array[1..100]of integer;
 b:array[1..100]of point;
 n:integer;
 min:longint;
procedure ini;
var i,j:integer;
begin
 assign(input,'cowties.in');assign(output,'cowties.out');
 reset(input);rewrite(output);
 readln(n);
 for i:=1 to n do begin
  read(s[i]);
  for j:=1 to s[i] do read(a[i,j].x,a[i,j].y);
  readln;
 end;
 fillchar(map,sizeof(map),true);
 min:=999999999;
end;
procedure search(dep:integer);
var i,j:integer;tot:real;
begin
 if dep=n+1 then begin
  tot:=0;
  for i:=2 to n do
   tot:=tot+sqrt(sqr(b[i].x-b[i-1].x)+sqr(b[i].y-b[i-1].y));
  tot:=tot+sqrt(sqr(b[1].x-b[n].x)+sqr(b[1].y-b[n].y));
  if trunc(tot*100)<min then min:=trunc(tot*100);
 end
 else begin
  for i:=1 to s[dep] do
   if map[a[dep,i].x,a[dep,i].y] then begin
    map[a[dep,i].x,a[dep,i].y]:=false;
    b[dep].x:=a[dep,i].x;
    b[dep].y:=a[dep,i].y;
    search(dep+1);
    map[a[dep,i].x,a[dep,i].y]:=true;
   end;
 end;
end;
begin
 ini;
 search(1);
 write(min);
 close(input);close(output);
end.