Number of Digit One LeetCode solution in Java

1
class Solution {
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  int max(int a, int b) {
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    if (a > b) return a;
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    else return b;
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  }
6

7
  int min(int a, int b) {
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    if (a > b) return b;
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    else return a;
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  }
11

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  public int countDigitOne(int n) {
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    int c = 0;
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    for (int i = 1; i <= n; i *= 10) {
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      int divider = i * 10;
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      c += (n / divider) * i + min(max((n % divider - i + 1), 0), i);
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    }
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    return c;
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  }
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}
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// T.C.  - O(log n)