Design an ATM Machine LeetCode solution in Java

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class ATM {
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  long[] notes =
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      new long[5]; // Note: use long[] instead of int[] to avoid getting error in large testcases
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  int[] denoms;
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  public ATM() {
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    denoms = new int[] {20, 50, 100, 200, 500}; // create an array to represent money value.
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  }
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  public void deposit(int[] banknotesCount) {
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    for (int i = 0; i < banknotesCount.length; i++) {
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      notes[i] += banknotesCount[i]; // add new deposit money to existing
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    }
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  }
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  public int[] withdraw(int amount) {
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    int[] result =
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        new int
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            [5]; // create result array to store quantity of each notes we will be using to withdraw
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    // "amount"
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    for (int i = 4; i >= 0; i--) {
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      if (amount >= denoms[i]) {
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        int quantity =
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            (int)
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                Math.min(
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                    notes[i],
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                    amount
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                        / denoms[
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                            i]); // pick the minimum quanity. because if say, amount/denoms[i] gives
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        // 3 but you only have 1 note. so you have to use 1 only instead of
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        // 3
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        amount -= denoms[i] * quantity; // amount left = 100
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        result[i] = quantity;
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      }
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    }
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    if (amount != 0) {
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      return new int[] {-1};
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    }
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    for (int i = 0; i < 5; i++) {
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      notes[i] -= result[i];
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    } // deduct the quantity we have used.
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    return result;
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  }
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}