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class Stocks implements FundConstants {
    static int[] balances =
                       new int[noOfStocks];
    static Object[] locks =
                    new Object[noOfStocks];
    static
    {
        for (int n=0; n<noOfStocks; n++) {
            balances[n] = 10000;
            locks[n] = new Object();
        }
    }

    static void transfer(Transfer t) {
        int lo, hi;
        if (t.fundFrom > t.fundTo) {// acquires the monitors in decreasing numeric order
            lo = t.fundFrom;
            hi = t.fundTo;
        } else {
            lo = t.fundTo;
            hi = t.fundFrom;
        }
        synchronized (locks[lo]) {
            synchronized (locks[hi]) {
                balances[t.fundFrom] -= t.amount;
                balances[t.fundTo] += t.amount;
            }
        }
    }

    static int sumHelper (int next) {
        synchronized (locks[next]) {
            if (next == (noOfStocks-1)) {
                return balances[next];
            } else {
                return balances[next] +
                       sumHelper(next+1);
            }
        }
    }

    static void checkSystem() {
        int actual = 0;
        actual = sumHelper(0);
        System.out.println("Actual balance is
                                   " + actual);
    }
}