#!/usr/bin/perl -P
#define enter exit
#define p (1<<9)
#define write print
for(;@i["]<@i;++$i){--$i;}"]++|@i["]<@i;++$i){--$i;}"]?++$i:$i;$i%2?pread($i,"Hello World"):$i>p?enter:$i){}write("\xd");sub pread(){my($a)=@_;write($a);}

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