Made queen solution pick a random one to load, trace queen also picks random one, but diffrently (just cahnged starting pos)

app/routes/main_routes.py

@@ -178,7 +178,10 @@ def build_queens_trace(board_size):
             })
             return True
 
-        for col in range(board_size):
+        candidate_columns = list(range(board_size))
+        random.shuffle(candidate_columns)
+
+        for col in candidate_columns:
             if not is_queen_position_safe(row, col):
                 continue
 
@@ -374,9 +377,14 @@ def check():
 
 @main_bp.route("/solve")
 def solve_queens_route():
-    """Return all queens solutions for the requested board size."""
+    """Return one random queens solution for the requested board size."""
     board_size = parse_board_size(request.args.get("size"))
-    return jsonify(solve_queens(board_size))
+    queen_solutions = solve_queens(board_size)
+
+    if not queen_solutions:
+        return jsonify([])
+
+    return jsonify(random.choice(queen_solutions))
 
 
 @main_bp.route("/solve_trace")

test/test_app_integration.py

@@ -75,6 +75,16 @@ def test_check_endpoint_applies_different_rules_for_queens_and_rooks(client):
     assert rooks_response.get_json() == {"valid": True}
 
 
+def test_solve_endpoint_returns_one_valid_4x4_queens_solution(client):
+    response = client.get("/solve?size=4")
+
+    assert response.status_code == 200
+    assert tuple(response.get_json()) in {
+        (1, 3, 0, 2),
+        (2, 0, 3, 1),
+    }
+
+
 def test_authenticated_user_can_save_and_load_a_game_state(client, app_instance, user_factory, login_as):
     user_factory(username="alice", password="Password123!")