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class Solution {
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  public boolean splitString(String s) {
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    return isRemainingValid(s, null);
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  }
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  private boolean isRemainingValid(String s, Long previous) {
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    long current = 0;
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    for (int i = 0; i < s.length(); i++) {
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      current = current * 10 + s.charAt(i) - '0';
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      if (current >= 10000000000L) return false; // Avoid overflow
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      if (previous == null) {
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        if (isRemainingValid(s.substring(i + 1), current)) return true;
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      } else if (current == previous - 1
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          && (i == s.length() - 1 || isRemainingValid(s.substring(i + 1), current))) return true;
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    }
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    return false;
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  }
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}