Re^3: Control loop 2D array

Not very satisfying because of the need to use a 'goto' to quit the loops early, and the need to duplicate the index vars because Perl localises them to loop even if they are pre-existing vars.

I tried suggesting that the latter behaviour was a bug a while ago and got shouted down.

#! perl -slw
use strict;

my @AoA = (
   [ '1', '2', '11' ],
   [ '3', '3', '6'  ],
   [ '6', '8', '11'  ],
   [ '0', '7',  '9'  ],
);

my @A = qw(0 0 0 0 1 2 0 0 1 0 1 0);

my( $p, $q );
OUTER: for my $i ( 0 .. $#AoA ) {
    for my $j ( 0 .. $#{ $AoA[ $i ] } ) {
        ( $p, $q ) = ( $i, $j ) and last OUTER
            if $A[ $AoA[ $i ][ $j ] ];
    }
}
print "i:$p j:$q";
[download]

I'm not sure why you are using the outer loop below?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

Comment on Re^3: Control loop 2D array Download Code

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Re^4: Control loop 2D array by ysth (Canon) on Jun 17, 2007 at 16:54 UTC
I'm not sure why you are using the outer loop below? A different interpretation of "the first occurence to in the second array is not zero"; mine prints 1 1. No idea which interpretation (if either) is actually what is wanted. I like that your new version reports undefs instead of (@AoA, 0) if there is no match.	[reply]
Re^5: Control loop 2D array by BrowserUk (Patriarch) on Jun 17, 2007 at 18:59 UTC
Looking back at the OP, I can now see the other interpretation. Good point++ on the no match scenario. Updated above. Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply]