30 lines
616 B
Perl
30 lines
616 B
Perl
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%hash = ( Karl => 2,
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Joe => 3,
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Shawn => 0,
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Paul => 1,
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Bill => undef );
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# obtain the list of hashKeys and display each key-value pair
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@hashKeys = keys( %hash );
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for ( $i = 0; $i < @hashKeys; ++$i ) {
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print "$hashKeys[ $i ] => $hash{ $hashKeys[ $i ] }\n";
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}
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delete( $hash{ 'Joe' } );
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while ( $key = pop( @hashKeys ) ) {
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print "\n";
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# determine if the value for the key is defined
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if ( defined( $hash{ $key } ) ) {
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print "$key is defined as $hash{ $key }.\n";
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}
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else {
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print "$key is undefined.\n";
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}
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}
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