#!/usr/bin/perl -l

    use strict;

    sub powa2 
    {
    ;      local %_ = @_
    ;      keys  %_ = pop
    ;      $_ =  %_
    ;      split '\/'
    ;      pop
    }


    __END__
    print powa2(63);   # prints 64
    print powa2(64);   # prints 64
    print powa2(65);   # prints 128
    print powa2(1234); # prints 2048
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--
John.