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Reading Assignment and Discussion Topics
Computer Science 111

for class on Thursday Feb. 24, 2000

Please read Sections 4.1 and 4.2 up to page 129 of the Schneider and Gersting text, paying particular attention to the representation of positive binary integers. Be prepared to discuss the following:

Here's an idea for adding two binary numbers: first, convert them to decimal; next, add the decimal numbers; finally, convert the answer back to binary. How about a less circuitous method? How might you add the binary numbers directly? When you add decimal numbers you doubtless rely on a table that was drilled into your head in grade school: you "know" that 7+5=12 by consulting your mental table. Well, binary adding probably reqires a table too. Don't forget the carries! Let's use a currently popular width for these numbers: 32 bits, just like the insides of your lab PC's.