function get_neighbour(cell){

	var x = getCellX(cell) ;
	var y = getCellY(cell) ;
	var neighbours = [] ;

	for(var i=-1;i<1;i+=2){
		for(var j=-1;j<1;i+=2){
			if(abs(x+i)+abs(y+1) <= 17){
				var sub_cell = getCellFromXY(x+i, y+j) ;
				if(!isObstacle(sub_cell)
					or !isLeek(sub_cell)){
					push(neighbours, sub_cell) ;
				}
			}
		}
	}
	return neighbours ;
}