in reply to Re: How do I find the Nth occurrence of a pattern?
in thread How do I find the Nth occurrence of a pattern?

I have to correct my code. I passed in a reference and never used it :(. 
#!/usr/bin/perl -w
my @string = (34, 56, 78, 90, 98, 76, 54, 32, 10, 12, 13, 16, 19, 20, 
+10, 56);
 
sub nth_iter{
    my ($item, $n, $list) = @_;
    ( map { $list->[$_] == $item ? $_ : (); } 0..$#$list )[--$n] or -1
+;
}
 
print nth_iter(78, 1, \@string);

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RE: RE: Answer: How do I find the Nth occurrence of a pattern?
by eak (Monk) on Aug 06, 2000 at 19:20 UTC
    Now using grep...speeed!! 
    #!/usr/bin/perl -w
 
my @string = (34, 56, 78, 90, 98, 76, 54, 32, 10, 12, 13, 16, 19, 20, 
+10, 56);
 
sub nth_iter{
  my ($item, $n, $list) = @_;
  ( grep  $list->[$_] == $item,  0..$#$list )[--$n] or -1;
}
 
print nth_iter(10, 3, \@string);

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