Honey Donuts

Board & Pieces
3 pieces including one King, and the same 3 for blue and 12 white pieces are initially placed on a Honey Donut board.

Movements
Players move their pieces in their turn following the rules below:
Move a whole "straight line" of pieces which includes his/her piece(s) one square in either direction along the line. "Straight lines" are composed of either 2, 3 or 4 pieces. All the pieces in one "straight line" need to be moved always together.
With the move, one piece is pushed out from the board. The pushed out piece is placed in the square in which no piece is placed after the move. The King pieces cannot be placed back on the board as it is the end of the game when they are pushed out of the board.
Moving the line backward right after the opponent's turn is not allowed.
No pass is allowed.

Goal
The player who pushed opponent's King out of the board wins.