Hi Monks
I have a file with lines that look like this:
1  ahjewgfje
1  gopjregre
2  kkkkkkk
3  figjiorger
3  rekopfroeer
3  ejfjviknced
4  erjgirjgerio
5  eieuiee
5  reopjtfrpeoi

[download]

Can you help me to keep only these lines in which the preceding number appears only once? In the example above, I would keep the lines starting with 1,3 and 5.

In reply to Remove unique lines from file by Anonymous Monk

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