Slides: Review

class: title
# Review
## CSC 161 – March  3, 2026

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# Agenda for Today
1. Department Events
2. Upcoming Work
3. Review
4. Wrap Up

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# Department Events

## CS Table: LLM-Mediated Computing
.indent[
  Tuesday, March 3rd at noon in JRC 224C
]

<img alt="A QR code for the poster session registration URL linked above" src="../files/poster_session_qr.png" width="250em" style="float: right">
## CS Poster Sessions
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  Wednesday, April 8th and Thursday, April 9th, 4:15pm–5:45pm  
  Register to present at <https://tinyurl.com/CS-Posters-26S>
]

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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# Exam 1
In class on Thursday, March 5th

## Policies
- You will have the full 110min class period to take the exam.
- I will provide scratch paper and a scientific calculator.
- You can bring a two-sided 8.5x11" sheet of *hand written* notes.
- You may not use any other resources on the exam.

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# Exam 1 Topics

The exam will cover material through week six.
Topics may include:
.left-col[
- Variables and Types
- C Statements and Expressions
- Loops
- Conditionals
- Functions
- Pointers
- Arrays
- Strings
]
.right-col[
- Structs
- Enums
- Unsigned Binary Integers
- Two's Complement Binary Integers
- Floating Point Representation
- Multifile Projects
- Makefiles
- Debugging and Testing
]

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# Review

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# Review: Checking for Palindromes

Complete the function below:

```c
bool is_palindrome(char* message) {
   int length = strlen(message);
   ...
```

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# Review: Name That Function

Suggest a better name for the function, parameters, and variable in the code below, and then explain how the function works.

```c
int w(char* x, char* y) {
   int z = 0;
   while (x[z] == y[z] && x[z] != '\0') {
      z++;
   }
   return x[z] - y[z];
}
```

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# Review: Multiplying Complex Numbers

The `struct complex` type represents a complex number:

```c
struct complex {
   float real;
   float imaginary;
};
```

Write functions `complex_add` and `complex_multiply` that add and multiply complex numbers.

```c
struct complex complex_add(struct complex a, struct complex b);
struct complex complex_multiply(struct complex a, struct complex b);
```

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# Review: Number Representation

The signed 8-bit integer variable `x` is defined as follows:
```c
int8_t x = 0b11111100;
```

*Note: the `int8_t` type is guaranteed to be a signed 8-bit integer, which usually means it is a `char`.*

When we assign an integer to a `float` (as in the following code fragment), C will implicitly convert the integer to an equivalent floating point value.
The two variables will have very different binary representations even though they represent the same number.

```c
float y = x;
```

***What is the binary representation of `y`?***

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# Review: Makefiles and Multifile Projects

.left-col[
Consider a program with three `.c` files and two `.h` files:
- `x.c` includes `y.h` and `z.h`
- `y.c` includes `y.h`
- `z.c` includes `z.h`

We can compile the whole program with this command:
```shell
$ clang -o program x.c y.c z.c
```
]

.right-col[
## Problems
1. Write a single `Makefile` rule that runs the command above any time the program needs to be updated.

2. Rewrite the compilation command above as a series of commands to perform *separate compilation*.

3. Write a `Makefile` that can perform the separate compilation steps for you automatically.
]

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# Wrap Up

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# Wrap Up

## Mentor Session
Want some extra practice before the exam?
Attend tomorrow's mentor session from 7-9pm.

## Exam Note Sheet
Don't forget, you can bring a two-sided 8.5"x11" sheet of hand-written notes for the exam on Thursday.