open my $fh, '<', 'whatever'; # or whatever my %hash = ( a => 0, e => 1, i => 2, o => 3, u => 4 ); while ( <$fh> ) { chomp; my $copy = $_; my @array; while ( my $char = lc chop $copy ) { no warnings 'uninitialized'; $array[ $hash{ $char } ] = 1; } say if ( grep $_, @array ) == 5; }