Slides: Representing Numbers

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# Representing Numbers
## CSC 161 – February 19, 2026

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# Agenda for Today
1. Quiz
2. Department Events
3. Upcoming Work
4. Discussion
5. Lab
6. Wrap Up

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# Quiz

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# Department Events

## CS Extra: Tarski Lower Bounds from Multi-Dimensional Herringbones
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  Speaker: Reed Phillips, Purdue University  
  Thursday, February 19th at 4:15pm in Noyce 3821  
  Snacks available in the CS Commons at 4pm
]

You can find a complete list of token events and submit more at <https://tinyurl.com/csc161-tokens>.

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# Upcoming Work

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# Homework: Connect Four
**Due:** Thursday, February 26th

## Questions
_None so far_

If you need to work on the assignment from off campus you can access a MathLAN session by going to <https://remote.cs.grinnell.edu>.

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# Discussion

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# Discussion: Integer Representation
**Items for think, pair, share:**

1. What is the difference between signed and unsigned integers?

2. What value does the eight-bit binary value `10010110` represent if we interpret it as...
   - An unsigned integer
   - A sign-magnitude integer
   - A one's complement integer
   - A two's complement integer

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# Discussion: Floating Point Representation
**Items for think, pair, share:**

1. Floating point values have a sign bit, exponent, and mantissa.
   What do these three parts of the number represent?

2. We can write the value 10 as 1.25 x 2<sup>3</sup>.
   Using this information, how do we represent the floating point value `10.0` in binary?

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# Lab

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# Wrap Up

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# Wrap Up

## Lab Work
Submit all exercises for parts A and C, along with one of the three exercises form part B (you may choose any of the three).

## Reading

- **Multifile Projects** (Beej's Guide to C Programming, Chapter 17)
              
            
              
- **An Introduction to Makefiles** (GNU Make Manual, Chapter 2)