program task11;

{$APPTYPE CONSOLE}


var x,y,r:array[0..100]of integer;
    i,j,n,min,ii,jj:integer; s,p:real;

function ff(ii,i:integer):boolean;
var k,j:Integer;
begin
  ff:=false;
  k:=0;
  for j:=1 to n do
  if (((x[i]-x[ii])*(y[j]-y[ii])-(y[i]-y[ii])*(x[j]-x[ii]))<=0) and(j<>i)and(i<>ii)and(j<>ii)then k:=k+1;
  if k=n-2 then ff:=True;
  end;




begin
    assign(input,'task11.in');
    reset(input);
    read(n);
    for i:=1 to n do read(x[i],y[i]);
    close(input);
    min:=0;x[0]:=MaxInt;
    for i:=1 to n do if x[i]<x[min] then min:=i;
    //for i:=1 to n do Writeln(x[i]);
     //Writeln(x[min],y[min]);
   

        jj:=1; r[jj]:=min;
      ii:=min; i:=MaxInt;
     while (i<>min)do begin
        i:=1;
        while not(ff(ii,i)) do begin
         // writeln(ii,' ',i);
          i:=i+1;
        end;

        jj:=jj+1;
        r[jj]:=i;
        ii:=i;
      end;

s:=0; p:=0;
for i:=1 to jj-1 do
begin
s:=s+x[r[i]]*y[r[i+1]]-x[r[i+1]]*y[r[i]];
p:=p+sqrt(sqr(x[r[i]]-x[r[i+1]])+sqr(y[r[i]]-y[r[i+1]]));
end;
s:=abs(s)/2;

assign(output,'task11.out');
rewrite(output);
for i:=1 to jj do writeln(r[i]);
writeln(p:0:2);
writeln(s:0:2);
close(output);
end.