foreach (@pwds) {
        $i++;
        
        next unless $_ =~ m/$grep/;
        $_ =~ m/(.*?) - (.*?) \((.*?)\)/;

        print "Delete '$1'? [y/n] ";
        chop(my $command = <STDIN>);
        next unless $command eq 'y';

        splice(@pwds, $i, 1);
    }
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From the "Foreach Loops" section of perlsyn:

If any part of LIST is an array, "foreach" will get very confused if you add or remove elements within the loop body, for example with "splice". So don't do that.