Catch Diamond

This is a game with surrounding and blocking.
At first,system initialization on the Board with 1 diamonds and 7-8 pieces belonging to player ,
then the players set up, then the diamonds move one step, if the player circled the diamond, then the player wins, but it's not easy to win.
on the contrary, if the diamonds are moved out of the Board, then the player fails.

Rules of the game:
1. Tap on the gray blank area to set up.
2. Diamond moves automatically step to adjacent places after you set up.
3. repeat step 1 and step 2 until one side WINS.
4. Use as less number of steps to circled the diamond as you can.