1
var largestVariance = function (s) {
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  let chars = new Set(s.split("")),
3
    maxDiff = 0;
4
  for (let l of chars) {
5
    for (let r of chars) {
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      if (l === r) continue;
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      let lCount = 0,
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        rCount = 0,
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        hasRight = false;
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      for (let char of s) {
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        lCount += char === l ? 1 : 0;
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        rCount += char === r ? 1 : 0;
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        if (rCount > 0 && lCount > rCount) {
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          // has both characters and positive difference
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          maxDiff = Math.max(maxDiff, lCount - rCount);
16
        }
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        if (lCount > rCount && hasRight) {
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          // has positive difference and a previous "right" character we can add to the start
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          maxDiff = Math.max(maxDiff, lCount - rCount - 1);
20
        }
21
        if (lCount < rCount) {
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          (lCount = 0), (rCount = 0);
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          hasRight = true;
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        }
25
      }
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    }
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  }
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  return maxDiff;
29
};