print <<EOF;
ABCDEFGFEDCBA   
ABCDEF FEDCBA   
ABCDE   EDCBA   
ABCD     DCBA   
ABC       CBA    
AB         BA  
A           A
EOF
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$a = "ABCDEFGFEDCBA\n";  
print($a), substr($a, 7-$_, 2*$_-1) = " " ."  " x ($_-1) for  1..7
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