n,i,j,k,t:longint;
s,x:double;
begin
readln(n);
for i:=1 to n do begin
read(a[i,1],a[i,2],a[i,3],a[i,4]);
if a[i,1]>a[i,3] then begin
t:=a[i,1];a[i,1]:=a[i,3];a[i,3]:=t;
end;
if a[i,2]>a[i,4] then begin
t:=a[i,2];a[i,2]:=a[i,4];a[i,4]:=t;
end;
end;
x:=100000000;
for i:=0 to 100 do begin
for j:=0 to 100 do begin
s:=0;
for k:=1 to n do begin
t:=0;
if a[k,1]=a[k,3] then begin
if (j>=a[k,2]) and (j<=a[k,4]) then begin
s:=s+abs(i-a[k,1]);
end
else begin
if abs(j-a[k,4])>abs(j-a[k,2]) then t:=j-a[k,2] else t:=j-a[k,4];
s:=s+sqrt((i-a[k,1])*(i-a[k,1])+t*t);
end;
end
else begin
if (i>=a[k,1]) and (i<=a[k,3]) then begin
s:=s+abs(j-a[k,2]);
end
else begin
if abs(i-a[k,1])>abs(i-a[k,3]) then t:=i-a[k,3] else t:=i-a[k,1];
s:=s+sqrt((j-a[k,2])*(j-a[k,2])+t*t);
end;
end;
end;
if s<x then x:=s;
end;
end;
write(x:0:2);
end.