Count of Smaller Numbers After Self LeetCode solution in Java

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class Solution {
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  public List<Integer> countSmaller(int[] nums) {
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    int min = 20001;
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    int max = -1;
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    for (int num : nums) {
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      min = Math.min(min, num);
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      max = Math.max(max, num);
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    }
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    min--;
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    int[] count = new int[max - min + 1];
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    Integer[] result = new Integer[nums.length];
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    for (int i = nums.length - 1; i >= 0; i--) {
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      int k = nums[i] - min - 1;
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      int c = 0;
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      do {
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        c += count[k];
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        k -= (-k & k);
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      } while (k > 0);
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      result[i] = c;
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      k = nums[i] - min;
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      while (k < count.length) {
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        count[k]++;
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        k += (-k & k);
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      }
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    }
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    return Arrays.asList(result);
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  }
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}