public Coordinate determineWumpus(List<Coordinate> _visited){
        //Get all visited stenches.
        List<Coordinate> stenches = new ArrayList<>();
        
        for (Coordinate v : _visited) {
            if(world.hasStench(v.x, v.y))
                stenches.add(v);
        }
        List<Coordinate> validWumpusSpots = new ArrayList<>();
        Map<Coordinate, Integer> commonSquares = new HashMap<>();
        for (Coordinate v : stenches) {
            //Get surrounding squares for each stench
            List<Coordinate> surrounding = getSurroundingSquares(v);
            for (Coordinate u : surrounding) {
                //If visited it's assumed to be safe.
                if(world.isVisited(u.x, u.y)){
                    continue;
                }
                if(!commonSquares.containsKey(u)){
                    commonSquares.put(u, 1);
                }
                else{
                    int value = commonSquares.get(u);
                    commonSquares.put(u, value + 1);
                }
            }
        }
        //Any common squares?
        for(Map.Entry<Coordinate, Integer> entry : commonSquares.entrySet()) {
            if(entry.getValue() > 1)
                validWumpusSpots.add(entry.getKey());
        }
        //One common square -> wumpus found.
        if(validWumpusSpots.size() == 1){
            return validWumpusSpots.get(0);
        }
        else{
            //Not found, return invalid pos
            return new Coordinate(-1, -1);
        }
    }