#include <iostream>
#include <fstream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <iomanip>
using namespace std;
struct line {
   float x[ 2 ], y[ 2 ];
};
line a[ 100 ];
int n;
float dp[ 30 ][ 35000 ];
float dist( float x1, float x2, float y1, float y2 ) {
   return sqrt( ( x1 - x2 ) * ( x1 - x2 ) + ( y1 - y2 ) * ( y1 - y2 ) );
}
int main() {
   cin >> n;
   for( int i = 0; i < n; i ++ ) {
      cin >> a[ i ].x[ 0 ] >> a[ i ].y[ 0 ] >> a[ i ].x[ 1 ] >> a[ i ].y[ 1 ];
   }
   for( int i = 0; i < 30; i ++ ) {
      dp[ i ][ 0 ] = 0;
   }
   for( int i = 0; i < n; i ++ ) {
      for( int j = 0; j < 2; j ++ ) {
         int cur = i * 2 + j;
         for( int k = 1; k < ( 1 << n ); k ++ ) {
            if( k & ( 1 << i ) ) {
               continue;
            }
            dp[ cur ][ k ] = 1000000000;
            float mini = dp[ cur ][ k ], best;
            for( int b = 0; b < n; b ++ ) {
            if( ! ( k & ( 1 << b ) ) )
               continue;
            float oldmi = mini;
            mini = min( mini, dp[ 2 * b ][ k ^ ( 1 << b ) ] + dist( a[ b ].x[ 0 ], a[ i ].x[ j ], a[ b ].y[ 0 ], a[ i ].y[ j ] ) + dist( a[ b ].x[ 0 ], a[ b ].x[ 1 ], a[ b ].y[ 0 ], a[ b ]. y[ 1 ] ) );
            mini = min( mini, dp[ 2 * b + 1 ][ k ^ ( 1 << b ) ] + dist( a[ b ].x[ 1 ], a[ i ].x[ j ], a[ b ].y[ 1 ], a[ i ].y[ j ] ) + dist( a[ b ].x[ 0 ], a[ b ].x[ 1 ], a[ b ].y[ 0 ], a[ b ]. y[ 1 ] ) );
            if( oldmi != mini )
               best = b;
            }
            dp[ cur ][ k ] = mini;
            if( __builtin_popcount( k ) == n - 1 ) {
               cout << dp[ cur ][ k ] << '\n';
            }
         }
      }
   }
   return 0;
}