Count Numbers with Unique Digits LeetCode solution in Java

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class Solution {
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  public int countNumbersWithUniqueDigits(int n) {
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    /*
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        9 * 9 + 10 for n = 2
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           9 * 9 * 8 + 10 for n = 3
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           9 * 9 * 8 * 7 + 10 for n = 4
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           9 * 9 * 8 * 7 * 6 + 10 for n = 5
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    */
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    if (n == 0) return 1;
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    if (n == 1) return 10;
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    int product = 9;
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    int result = 10;
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    for (int i = 2; i <= n; i++) {
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      product = product * (11 - i);
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      result += product;
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    }
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    return result;
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  }
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}