sendFishes(int start)

    int sendFishes(int start) {

        LinkedQueue<Integer> pom = new LinkedQueue<Integer>();
        int count = 0;
        boolean checked[] = new boolean[num_nodes];
        for (int i = 0; i < checked.length; i++) {
            checked[i] = false;
        }

        pom.enqueue(start);
        checked[start] = true;

        while (!pom.isEmpty()) {
            int tmp = pom.dequeue();
            count++;

            for (int i = 0; i < num_nodes; i++) {
                if (adjMat[tmp][i] == 1) {
                    if (!checked[i]) {
                        pom.enqueue(i);
                        checked[i] = true;
                    }
                }
            }
        }

        return count-1;

    }