$usage_grpinf[2] may be undefined or contains spaces/characters.

add "use strict" or/and "use warnings". If $usage_grpinf[2]is undefined, it will give such warnings when you execute the program.

also try printing $usage_grpinf[2] enclosed in brackets so you'll know if it contains spaces or newlines i.e.
print "usage_grpinf[2] : |$usage_grpinf[2]|\n";

In reply to Re: how can i check an array element as empty or not by susanti13
in thread how can i check an array element as empty or not by Anonymous Monk

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