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/**
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 * @param {string} text
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 * @return {number}
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 */
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const getLast = (ar) => ar[ar.length - 1];
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var maxRepOpt1 = function (text) {
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  let freq = {};
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  // compute frequency map
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  for (let i = 0; i < text.length; i++) {
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    let e = text[i];
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    !freq[e] && (freq[e] = 0);
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    freq[e]++;
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  }
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  let segments = [];
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  segments.push({
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    v: text[0],
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    c: 1,
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  });
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  let max = 1;
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  for (let i = 1; i < text.length; i++) {
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    let e = text[i];
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    let last = getLast(segments);
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    if (last.v == e) {
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      last.c++;
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      max = Math.max(max, last.c);
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    } else {
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      segments.push({ v: e, c: 1 });
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    }
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  }
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  for (let i = 0, len = segments.length; i < len; i++) {
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    let { v, c } = segments[i];
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    if (freq[v] > c) {
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      // x x a , a x x , x a x
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      max = Math.max(max, c + 1);
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    }
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    if (i + 2 < len && v == segments[i + 2].v) {
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      // x a x a x a x a x x a x a
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      let sum = c + segments[i + 2].c;
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      if (segments[i + 1].c == 1) {
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        if (freq[v] > sum) {
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          max = Math.max(max, 1 + sum);
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        } else {
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          max = Math.max(max, sum);
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        }
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      }
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    }
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  }
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  return max;
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};