Minimum Number of Flips to Make the Binary String Alternating LeetCode solution in Java

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class Solution {
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  public int minFlips(String s) {
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    /*
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     * Sliding Window Approach
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     */
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    int n = s.length();
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    int mininumFlip = Integer.MAX_VALUE;
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    int misMatchCount = 0;
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    for (int i = 0; i < (2 * n); i++) {
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      int r = i % n;
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      // add mis watch count in current window
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      if ((s.charAt(r) - '0') != (i % 2 == 0 ? 1 : 0)) misMatchCount++;
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      // remove mismatch count which are not relvent for current window
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      if (i >= n && (s.charAt(r) - '0') != (r % 2 == 0 ? 1 : 0)) misMatchCount--;
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      // misMatchCount : when valid binary string start from 1
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      // n - misMatchCount : when valid binary string start from 0
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      if (i >= n - 1)
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        mininumFlip = Math.min(mininumFlip, Math.min(misMatchCount, n - misMatchCount));
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    }
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    return mininumFlip;
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  }
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}