diff options
| -rw-r--r-- | challenge-143/james-smith/perl/ch-1.pl | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/challenge-143/james-smith/perl/ch-1.pl b/challenge-143/james-smith/perl/ch-1.pl index 2b0c32a29a..9581393720 100644 --- a/challenge-143/james-smith/perl/ch-1.pl +++ b/challenge-143/james-smith/perl/ch-1.pl @@ -31,6 +31,7 @@ my @TESTS = ( [ '10 * 10 - 6 * 6 - 8 * 8', 0 ], [ '4 + 4 - 6 - 2', 0 ], [ '(10 + 10) * (10 - 10) * (10 + 10) * (20 - (((20))))', 0 ], + [ '(((((10+10)*10+10)*10+10)*10+10)*10+10)*10+10', 2111110 ], ); is( evaluate( $_->[0]), $_->[1] ) foreach @TESTS; @@ -42,9 +43,13 @@ cmpthese( 20000, { 'eval_rpn' => sub { evaluate_via_rpn($_->[0]) for @TESTS }, 'eval_hsh' => sub { evaluate_rpn_hsh($_->[0]) for @TESTS }, 'eval' => sub { eval( $_->[0]) for @TESTS }, + 'eval_x' => sub { eval_x( $_->[0]) for @TESTS }, }); done_testing(); +sub eval_x { + return eval( shift ); +} sub evaluate { my $str = shift; 1 while $str =~ s/\(\s*([^()]*?)\s*\)/ evaluate($1) /e; @@ -54,18 +59,17 @@ sub evaluate { } sub evaluate_via_rpn { - @s=();@o=(); - + @s=();@o=(); ## Stack/output for ( $_[0] =~ m{(-?\d+|[-+*()])}g ) { - if( m{\d} ) { + if( m{\d} ) { ## Number push to output push @o, $_; - } elsif( $_ eq '(' ) { - push @s, $_; - } elsif( $_ eq ')' ) { - push @o, $_ while ($_ = pop @s) ne '('; - } else { - push @o, pop @s while @s && $f{$s[-1]}[0] && $f{$_}[0]<=$f{$s[-1]}[0]; + } elsif( $_ eq '(' ) { # open bracket add to stack push @s, $_; + } elsif( $_ eq ')' ) { # close bracket + push @o, $_ while ($_ = pop @s) ne '('; # push everything to output (in reverse order) + } else { # until we reach the open bracket + push @o, pop @s while @s && $f{$s[-1]}[0] && $f{$_}[0]<=$f{$s[-1]}[0]; # pop off + push @s, $_; # and push to stack if higher precidence and push value to stack } } push @o, reverse @s; |