Hi japhy,

I'm trying to understand your updated regex: 

m{
  ^
  (?= \d* (\d) \d* \1 )
  (?! \d* \1 \d* \1 \d* \1 )
}x;

[download]
Could you explain what's going there? Tia :)

In reply to Re^2: Find duplicate digits by Anonymous Monk
in thread Find duplicate digits by Anonymous Monk

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