program firez;
uses math;
var x1,x2,y1,y2,c:array[1..40]of longint;
    t,k,m,n,i,j,z:longint;
    a,d:array[1..200,1..200]of real;
    b:array[1..200]of boolean;
    x,y:array[1..200]of longint;
    bo:array[-200..200,-200..200]of longint;
    p:array[1..200]of boolean;
    f:array[1..200]of real;
    s:real;
begin
assign(input,'firez.in');
reset(input);
assign(output,'firez.out');
rewrite(output);
readln(n);
fillchar(bo,sizeof(bo),0);
fillchar(p,sizeof(p),false);
for t:=1 to n do
  begin
    readln(x1[t],y1[t],x2[t],y2[t],c[t]);
    if (bo[x1[t],y1[t]]=0)and(bo[x2[t],y2[t]]=0) then
      begin
        a[z+1,z+2]:=c[t];
        a[z+2,z+1]:=c[t];
        x[z+1]:=x1[t];
        y[z+1]:=y1[t];
        x[z+2]:=x2[t];
        y[z+2]:=y2[t];
        bo[x1[t],y1[t]]:=z+1;
        bo[x2[t],y2[t]]:=z+2;
        z:=z+2;
      end
    else if bo[x1[t],y1[t]]=0 then
      begin
        k:=bo[x2[t],y2[t]];
        a[z+1,k]:=c[t];
        a[k,z+1]:=c[t];
        x[z+1]:=x1[t];
        x[z+2]:=y1[t];
        bo[x1[t],y1[t]]:=z+1;
        inc(z);
      end
    else if bo[x2[t],y2[t]]=0 then
      begin
        k:=bo[x1[t],y1[t]];
        a[z+1,k]:=c[t];
        a[k,z+1]:=c[t];
        x[z+1]:=x2[t];
        y[z+1]:=y2[t];
        bo[x2[t],y2[t]]:=z+1;
        inc(z);
      end
    else
      begin
        i:=bo[x1[t],y1[t]];
        j:=bo[x2[t],y2[t]];
        a[i,j]:=c[t];
        a[j,i]:=c[t];
      end;
    p[bo[x1[t],y1[t]]]:=true;
    p[bo[x2[t],y2[t]]]:=true;
  end;
fillchar(b,sizeof(b),false);
for t:=1 to n do
  for k:=t+1 to n do
    if (max(x1[t],x2[t])=max(x1[k],x2[k]))
      and(max(y1[t],y2[t])=max(y1[k],y2[k]))
      and(abs(x2[t]-x1[t])+abs(y2[t]-y1[t])=2)
      and(abs(x2[k]-x1[k])+abs(y2[k]-y1[k])=2) then
      begin
        inc(z);
        i:=bo[x1[t],y1[t]];
        j:=bo[x2[t],y2[t]];
        a[z,i]:=a[i,j]/2;
        a[i,z]:=a[z,i];
        a[z,j]:=a[i,z];
        a[j,z]:=a[i,z];
        i:=bo[x1[k],y1[k]];
        j:=bo[x2[k],y2[k]];
        a[z,i]:=a[i,j]/2;
        a[i,z]:=a[z,i];
        a[j,z]:=a[z,i];
        a[z,j]:=a[z,i];
      end;
for i:=1 to z do
  for j:=1 to z do
    d[i,j]:=a[i,j];
for k:=1 to z do
  for i:=1 to z do
    for j:=1 to z do
      if (i<>k)and(j<>k)and(i<>j)and(a[i,k]>0)and(a[k,j]>0)
        and((a[i,k]+a[k,j]<a[i,j])or(a[i,j]=0)) then
          a[i,j]:=a[i,k]+a[k,j];
for i:=1 to z do
  if p[i] then
  for j:=1 to n do
    begin
      t:=bo[x1[j],y1[j]];
      k:=bo[x2[j],y2[j]];
      if abs(a[i,t]-a[i,k])=d[t,k] then s:=max(a[i,t],a[i,k])
      else s:=max(a[i,t],a[i,k])+((d[t,k]-abs(a[i,t]-a[i,k]))/2);
      if s>f[i] then f[i]:=s;
    end;
s:=maxlongint;
for i:=1 to z do
  if (p[i])and(f[i]<s) then
    s:=f[i];
writeln(s:0:4);
close(output);
end.