notes/education/software development/ECE1400/C.md

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# Compilation Steps
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1. Preprocessing: The preprocessor obeys commands that begin with #, also known as directives
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Commands for the preprocessor are called directives. Directives begin with a pound sign, and they do not end with a semicolon.
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Example:
```c
#include <stdio.h>
```
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2. Compiling. A compiler translates then translates the program into machine instructions.
3. Linking: The generated objects are combined to create a complete executable.
The preprocessor is typically integrated with the compiler.
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# Types
## Strings
A string literal is characters enclosed in double quotation marks.
A newline can be inserted using `\n`.
## Integers
An integer is a way to store a whole number. In C, integers are signed by default.
## Floats
A float is a decimal value. Slower arithmetic and inexact values are both drawbacks of using floats.
## Variables
A variable must be declared before it is assigned.
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# Formatting specifiers
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# Standard library
## Formatting specifiers
| Specifier | Function |
| --------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `%d` | Decimal representation: Display a value as a base 10 (hence the decimal) integer. |
| `%f` | Fixed point decimal representation. Specify the number of places to round to by adding a decimal and a number, eg `%.2f` would round to two decimal places. |
| `%e` | |
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For number formatting specifiers, the convention is as follows:
`%-a.bX`
`%`: Start of the formatting specifier
`-`: (optional) If included, justify value left in space. Otherwise, justify right in space
`a`: (optional) If included, the size of the field in characters.
`.`: Separator between `a` and `b`. Optional if `b` is not specified
`b`: The number of decimal places to round to
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`X`: The type of format to use, and the end of the specifier. Use `d` for integer base 10 (decimal) representation, `f` for fixed point decimal, and `e` for exponential notation, and `g` to select between fixed point and exponential, whichever is shorter.
## `printf`
Write a string to standard output. `f` indicates that it's a formatting string. The string will not include move the cursor to a newline, append `\n` to the end of the string to do so.