How do you beat level 15 on B-Cubed

The way that you beat level 15 on B Cubed is the following:
You go to the left once, go up 3 blocks, turn onto the green square (top), go down to the green square (bottom), then turn right keep going up, turn left zigzag until the end, cross the bridge and go from there.

One solution is (hitting the top green first): L, U3, R, D2, R, U3, L4, D, R, D, L, D, R, D, L6, U, R, U, R2, D, L