Ok so try again with JSON::PP 
#!/usr/bin/env perl
use strict;
use warnings;
use CGI ();
use JSON::PP ();

my $q     = CGI->new;
my $data = $q->param('POSTDATA') || '{"a":100,"b":300}';

my $json  = JSON::PP->new->utf8;
my $input = $json->decode( $data );
my $a = $input->{a};
my $b = $input->{b};
my $c = $a + $b;

print $q->header("application/json");
print $json->encode({ c => $c });

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poj

In reply to Re^11: json return value by poj
in thread json return value by stenasc

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