private function tourIA(){

    var position = new List<Int>();
    for(i in 0...(Std.parseInt(Math.pow(dimensions,2)))position.add(i);

    var pos = Std.random(length(position);
    var cellule = position[pos];
    var x = cellule%dimensions;
    var y = Math.floor(cellule);
    var n : Navire = mer.chercherNavire(x , y);
    if (n != null) {
        mer.montrerNavire(n);
    }
    else{
        mer.placerCroix(mer, position, dimension);
    }
}