function tripLength(coordinates){
      let x1 = coordinates[0], y1 = coordinates[1];
      let x2 = coordinates[2], y2 = coordinates[3];
      let x3 = coordinates[4], y3 = coordinates[5];

      let AB = distance(x1,y1,x2,y2);
      let BC = distance(x2,y2,x3,y3);
      let AC = distance(x1,y1,x3,y3);

      if (BC == AB){
        console.log("1->2->3: " + (AB + BC));
      } else if (AC < AB && BC < AB){
        console.log("1->3->2: " + (AC + BC));
      } else if ((AB + BC) > (AB + AC)){
        console.log("2->1->3: " + (AB + AC))
      }

      function distance(x1,y1,x2,y2){
        let distance = Math.sqrt(Math.pow((x2-x1),2) + Math.pow((y2-y1),2));
        return distance;
      }
    }