static PlayOnBoard(board, move) {
board[move.vanish[0].x][move.vanish[0].y] = V.HOLE;
for (let psq of move.appear) board[psq.x][psq.y] = psq.c + psq.p;
static PlayOnBoard(board, move) {
board[move.vanish[0].x][move.vanish[0].y] = V.HOLE;
for (let psq of move.appear) board[psq.x][psq.y] = psq.c + psq.p;