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sub sum_of_fred_and_barney{ print "Hey,you called the sum_of_fred_and_barney subroutine.\n"; $fred+$Barney; print "I'm returning a value now.\n"; } $fred = 3; $barney = 4; $chr1 = &sum_of_fred_and_barney; print "$chr1\n"; $chr2 = 3 * &sum_of_fred_and_barney; print "$chr2\n"; 屏幕上看到的是()
A.
Hey,you called the sum_of_fred_and_barney subroutine. print "I'm returning a value now. 7 Hey,you called the sum_of_fred_and_barney subroutine. print "I'm returning a value now. 21
C.
Hey,you called the sum_of_fred_and_barney subroutine. print "I'm returning a value now. 1 Hey,you called the sum_of_fred_and_barney subroutine. print "I'm returning a value now. 3