A bird is tossing (flying to and fro) between two cars moving towards each other on a straight road. One car has speed of 27 km h^−1 while the other has the speed of 18 km h^−1. The bird starts moving from first car towards the other and is moving with the speed of 36 km h^−1 when the two were separated by 36 km. The total distance covered by the bird is