Pretty good, though you might want to rid yourself of those helpful variable names. Could also muddy up your data with obscure calculations. Finally make that loop a little less "text-book"... This should get you started:

#!/usr/bin/perl

@a=(10,32,33,74,97,99,101,104,107,108,110,111,112,114,115,116,117);
@b=(4,17,15,16,2,5,11,12,16,8,7,14,2,13,7,14,10,2,8,5,6,9,7,14,3,1);
print pack("C",$a[--$_]) for(@b);
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-Blake