UNIX Command Line

Input file:

$ cat cnr.txt
HIDDENHAUSEN|99.60
FIEBERBRUNN|99.07
MELLENDORF|99.04
HERBSTEIN|99.02
ACHTERWEHR|98.82
GOLM|98.82
PARA|98.82
BOGEN|98.61
SAINTANDRE|98.55
OLSZTYN|98.61
HYDERABAD|99.02

Output required: Print those lines for which 2nd field has occurred more than once. i.e. required o/p:

HERBSTEIN|99.02
ACHTERWEHR|98.82
GOLM|98.82
PARA|98.82
BOGEN|98.61
OLSZTYN|98.61
HYDERABAD|99.02

Awk solution:

$ awk 'NR==FNR && a[$2]++ {b[$2];next} $2 in b' FS="|" cnr.txt cnr.txt

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