Count and Say LeetCode solution in Java

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class Solution {
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  public String countSay(int n, String[] mapper) {
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    if (n == 1) return mapper[1];
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    else {
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      String say = "";
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      if (mapper[n - 1] != null) say += mapper[n - 1];
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      else say += countSay(n - 1, mapper);
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      String count = "";
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      int cache = Integer.parseInt(say.substring(0, 1));
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      int cntr = 1;
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      if (say.length() < 2) {
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        count += "1" + Integer.toString(cache);
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      } else {
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        for (int i = 1; i < say.length(); i++) {
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          if (cache == Integer.parseInt(say.substring(i, i + 1))) {
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            cntr++;
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            if (i == say.length() - 1) {
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              count += Integer.toString(cntr) + Integer.toString(cache);
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              cntr = 1;
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            }
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          } else {
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            count += Integer.toString(cntr) + Integer.toString(cache);
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            if (i < say.length() - 1) {
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              cache = Integer.parseInt(say.substring(i, i + 1));
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              cntr = 1;
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            } else if (i == say.length() - 1) {
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              count += "1" + say.substring(i, i + 1);
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            }
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          }
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        }
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      }
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      mapper[n] = count;
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      return mapper[n];
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    }
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  }
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  public String countAndSay(int n) {
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    String mapper[] = new String[n + 1];
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    mapper[1] = "1";
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    return countSay(n, mapper);
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  }
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}