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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 monitorslocks in increasing 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]) { // Acquires the monitorslocks in increasing numeric order
      if (next == (noOfStocks - 1)) {
        return balances[next];
      } else {
        return balances[next] + sumHelper(next + 1); // Increasing numeric order
      }
    }
  }

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