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Fixup flashcards.

c-declarations
Joshua Potter 2024-02-25 06:50:52 -07:00
parent 794e9a63ed
commit eb3cc5743a
12 changed files with 168 additions and 70 deletions
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22
notes/.obsidian/plugins/obsidian-to-anki-plugin/data.json
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@ -94,19 +94,19 @@
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@ -119,7 +119,7 @@
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@ -172,16 +172,16 @@
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@ -192,13 +192,15 @@
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},
"fields_dict": {
"Basic": [

11
notes/_journal/2024-02-25.md Normal file
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@ -0,0 +1,11 @@
---
title: "2024-02-25"
---
- [x] Anki Flashcards
- [ ] KoL
- [ ] Sheet Music (10 min.)
- [ ] OGS (1 Life & Death Problem)
- [ ] Korean (Read 1 Story)
- [ ] Interview Prep (1 Practice Problem)
- [ ] Log Work Hours (Max 3 hours)

8
notes/_journal/2024-02-24.md → notes/_journal/2024-02/2024-02-24.md
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@ -7,7 +7,7 @@ title: "2024-02-24"
- [ ] Sheet Music (10 min.)
- [x] OGS (1 Life & Death Problem)
- [ ] Korean (Read 1 Story)
- [ ] Interview Prep (1 Practice Problem)
- [x] Interview Prep (1 Practice Problem)
- [ ] Log Work Hours (Max 3 hours)
* Add back some notes on shifting in preparation of integer arithmetic.
@ -25,3 +25,9 @@ title: "2024-02-24"
* Q-127207
* Q-366042
* Q-144
* Notes on unsigned addition.
* Notes on `SIGILL`.
* Leetcode problems
* [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/description/)
* [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/description/)
* [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/description/)

16
notes/binary/integer-encoding.md
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@ -979,6 +979,22 @@ Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Program
<!--ID: 1708799678776-->
END%%
%%ANKI
Basic
Given integer $0 < x < 2^w$, what is $x$'s unsigned additive inverse?
Back: $2^w - x$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1708808252010-->
END%%
%%ANKI
Basic
Which unsigned integer is its own additive inverse?
Back: $0$
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
<!--ID: 1708808252017-->
END%%
## References
* Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.

64
notes/c17/strings.md
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@ -48,16 +48,18 @@ The syntax for the format placeholder is `%[flags][width][.precision][length]spe
%%ANKI
Basic
Which header file contains `printf` functionality?
Back: `stdio.h`
Which header file contains basic `printf` functionality?
Back: `<stdio.h>`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441467-->
END%%
%%ANKI
Cloze
{1:`width`} field specifies a {2:minimum} number of characters while {2:`precision`} specifies a {1:maximum}.
{1:`width`} specifies a {2:minimum} while {2:`precision`} specifies a {1:maximum}.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441472-->
END%%
@ -65,76 +67,85 @@ END%%
Cloze
The {`width` and `precision`} fields are output related whereas the {`length`} field is input related.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708425941269-->
END%%
Flag | Description
--------- | -----------
`-` | Left-aligns the output
`+` | Prepends a plus for positive signed-numeric types
`␣` | Prepends a space for positive signed-numeric types
`0` | Prepends zeros for numeric types
| Flag | Description |
| ---- | -------------------------------------------------- |
| `-` | Left-aligns the output |
| `+` | Prepends a plus for positive signed-numeric types |
| `␣` | Prepends a space for positive signed-numeric types |
| `0` | Prepends zeros for numeric types |
%%ANKI
Cloze
The {`-`} flag {left-aligns the output}.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756812-->
END%%
%%ANKI
Basic
What is the output of `printf("%-2d abc", 100)`?
Back: `100 abc`
Back: `100␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441477-->
END%%
%%ANKI
Basic
What is the output of `printf("%-4d abc", 100)`?
Back: `100 abc`
Back: `100␣␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441481-->
END%%
%%ANKI
Basic
What is the output of `printf("%.4d abc", 100)`?
Back: `0100 abc`
Back: `0100␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441486-->
END%%
%%ANKI
Basic
What is the output of `printf("%04d abc", 100)`?
Back: `0100 abc`
Back: `0100␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441491-->
END%%
%%ANKI
Basic
What is the output of `printf("%.4s abc", "efg")`?
Back: `efg abc`
Back: `efg␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441495-->
END%%
%%ANKI
Basic
What is the output of `printf("%.2s abc", "efg")`?
Back: `ef abc`
Back: `ef␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441499-->
END%%
%%ANKI
Basic
What is the output of `printf("%.2f abc", 0.01234)`?
Back: `0.01 abc`
Back: `0.01␣abc`
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441503-->
END%%
@ -143,6 +154,7 @@ Basic
How does the precision field affect `"%s"` parameters?
Back: Strings are truncated if longer than the specified precision.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441507-->
END%%
@ -151,6 +163,7 @@ Basic
How does the precision field affect `"%f"` parameters?
Back: Decimal values are truncated if longer than the specified precision.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441511-->
END%%
@ -159,6 +172,7 @@ Basic
What does a negative width field value indicate?
Back: This is actually a positive width with a `-` (left-align) flag.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708384441515-->
END%%
@ -167,6 +181,7 @@ Basic
The `-` `printf` flag overrides what default behavior?
Back: Output is right-aligned by default.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756840-->
END%%
@ -174,6 +189,7 @@ END%%
Cloze
The {`+`} `printf` flag {prepends a plus for positive signed-numeric types}.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756846-->
END%%
@ -182,6 +198,7 @@ Basic
The `+` `printf` flag overrides what default behavior?
Back: Nothing is prepended to positive signed-numeric types by default.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756852-->
END%%
@ -189,6 +206,7 @@ END%%
Cloze
The {`␣`} `printf` flag {prepends a space for positive signed-numeric types}.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756856-->
END%%
@ -197,6 +215,7 @@ Basic
The `␣` `printf` flag overrides what default behavior?
Back: Nothing is prepended to positive signed-numeric types by default.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756861-->
END%%
@ -205,6 +224,7 @@ Basic
How do the `+` and `␣` `printf` flags relate to one another?
Back: Both prepend a character to positive signed-numeric types.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756865-->
END%%
@ -213,6 +233,7 @@ Basic
What happens if both the `+` and `␣` `printf` flags are specified?
Back: The `+` flag takes precedence.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756870-->
END%%
@ -220,6 +241,7 @@ END%%
Cloze
The {`0`} `printf` flag {prepends zeros for numeric types}.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756875-->
END%%
@ -228,6 +250,7 @@ Basic
What option must be specified for the `0` `printf` flag to take effect?
Back: The "width" option.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756881-->
END%%
@ -236,6 +259,7 @@ Basic
The `0` `printf` flag overrides what default behavior?
Back: Spaces are used to match the "width" option by default.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1707918756888-->
END%%
@ -252,6 +276,7 @@ Basic
*Why* do length modifiers for e.g. `char` exist?
Back: For maximum portability in the face of default argument promotions.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673637-->
END%%
@ -259,6 +284,7 @@ END%%
Cloze
The {`hh`} length corresponds to the {`char`} type declaration.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673664-->
END%%
@ -266,6 +292,7 @@ END%%
Cloze
The {`h`} length corresponds to the {`short`} type declaration.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673668-->
END%%
@ -273,6 +300,7 @@ END%%
Cloze
The {`l`} length corresponds to the {`long`} type declaration.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673711-->
END%%
@ -280,6 +308,7 @@ END%%
Cloze
The {`ll`} length corresponds to the {`long long`} type declaration.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673719-->
END%%
@ -287,6 +316,7 @@ END%%
Cloze
The {`z`} length corresponds to the {`size_t`} type declaration.
Reference: “Printf,” in *Wikipedia*, January 18, 2024, [https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962](https://en.wikipedia.org/w/index.php?title=Printf&oldid=1196716962).
Tags: printf
<!--ID: 1708426673725-->
END%%
@ -494,8 +524,8 @@ END%%
Basic
Given `int64_t x`, why is `printf("%d", x)` a problem?
Back: `%d` matches an `int` which is not necessarily 64-bits.
Tags: printf
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
Tags: printf
<!--ID: 1708454462772-->
END%%

12
notes/combinatorics/combinations.md
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@ -56,14 +56,6 @@ Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n
<!--ID: 1708368078679-->
END%%
%%ANKI
Basic
How is a $k$-combination expressed recursively?
Back: Include or exclude a candidate, then find $(k - 1)$- or $k$-combinations on the remainder.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708369553051-->
END%%
%%ANKI
Basic
How is a $k$-combination of $n$ objects denoted?
@ -138,7 +130,7 @@ END%%
%%ANKI
Basic
*Why* are binomial coefficients "symmetric"
*Why* are binomial coefficients "symmetric"?
Back: The number of ways to choose $k$ objects is the same as the number of ways to *not* choose those $k$ objects.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708368078729-->
@ -459,7 +451,7 @@ END%%
%%ANKI
Basic
How many lattice paths exist from one corner of a chess board to the opposite corner?
Back: $\binom{16}{8}$
Back: $\binom{14}{7}$
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708384441440-->
END%%

4
notes/combinatorics/multiplicative-principle.md
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@ -55,7 +55,7 @@ END%%
%%ANKI
Basic
If $A$ is finite, how is $A \times B$ rewritten as $|A|$ disjoint sets?
If $A$ is finite, how is $A \times B$ rewritten as the union of $|A|$ disjoint sets?
Back: Given $A = \{a_1, \ldots, a_n\}$, $(\{a_1\} \times B) \cup \cdots \cup (\{a_n\} \times B)$.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708217738483-->
@ -63,7 +63,7 @@ END%%
%%ANKI
Basic
If $B$ is finite, how is $A \times B$ rewritten as $|B|$ disjoint sets?
If $B$ is finite, how is $A \times B$ rewritten as the union of $|B|$ disjoint sets?
Back: Given $B = \{b_1, \ldots, b_n\}$, $(A \times \{b_1\}) \cup \cdots \cup (A \times \{b_n\})$.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708217738487-->

8
notes/combinatorics/permutations.md
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@ -69,14 +69,6 @@ Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n
<!--ID: 1708451749781-->
END%%
%%ANKI
Basic
How is permutation expressed recursively?
Back: Put each candidate in the current position, finding all permutations of the remainder each time.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708369553046-->
END%%
%%ANKI
Basic
How is $n!$ permutations of $n$ objects derived?

30
notes/gawk/variables.md
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@ -95,12 +95,12 @@ END%%
* The separator used to distinguish records from one another.
* Defaults to `"\n"`.
`RS == ??` | Description
---------------------- | -------------------------------------
`"\n"` | Records are separated by the newline character. This is the default.
*any single character* | Records are separated by each occurrence of the character. Multiple successive occurrences delimit empty records.
`""` | Records are separated by runs of blank lines. Leading/trailing newlines in a file are ignored. If `FS` is a single character, then `"\n"` also serves as a field separator.
*regexp* | Records are separated by occurrences of characters that match *regexp*. Leading/trailing matches delimit empty records.
| `RS == ??` | Description |
| ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `"\n"` | Records are separated by the newline character. This is the default. |
| *any single character* | Records are separated by each occurrence of the character. Multiple successive occurrences delimit empty records. |
| `""` | Records are separated by one or more blank lines. Leading/trailing newlines in a file are ignored. If `FS` is a single character, then `"\n"` also serves as a field separator. |
| *regexp* | Records are separated by occurrences of characters that match *regexp*. Leading/trailing matches delimit empty records. |
%%ANKI
Cloze
@ -151,7 +151,7 @@ END%%
%%ANKI
Basic
How is `RS = ""` interpreted?
Back: `""` indicates runs of newlines should be treated as the record separator.
Back: `""` indicates one or more blank lines should be treated as the record separator.
Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. [https://www.gnu.org/software/gawk/manual/gawk.pdf](https://www.gnu.org/software/gawk/manual/gawk.pdf)
<!--ID: 1707829409163-->
END%%
@ -164,6 +164,22 @@ Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 202
<!--ID: 1707829409170-->
END%%
%%ANKI
Basic
What distinguishes `RS` value `""` and `\n`?
Back: The former separates on one or more *blank* lines, not just a newline character.
Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. [https://www.gnu.org/software/gawk/manual/gawk.pdf](https://www.gnu.org/software/gawk/manual/gawk.pdf)
<!--ID: 1708867924207-->
END%%
%%ANKI
Basic
What regexp is closest to mirroring `RS = ""` behavior?
Back: `\n\n+`
Reference: Robbins, Arnold D. “GAWK: Effective AWK Programming,” October 2023. [https://www.gnu.org/software/gawk/manual/gawk.pdf](https://www.gnu.org/software/gawk/manual/gawk.pdf)
<!--ID: 1708867924213-->
END%%
%%ANKI
Cloze
If `RS = ""` and `FS` is set to {a single character}, the {newline character} *always* acts as a field separator.

8
notes/logic/equiv-trans.md
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@ -215,7 +215,7 @@ END%%
%%ANKI
Basic
The term "equivalent" refers to a comparison between what two objects?
Back: Propositions.
Back: Expressions.
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707251673345-->
END%%
@ -579,7 +579,7 @@ END%%
%%ANKI
Basic
What identifier is guaranteed to not occur in $E_e^x$?
What identifier is guaranteed to not occur freely in $E_e^x$?
Back: None.
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707937867036-->
@ -587,7 +587,7 @@ END%%
%%ANKI
Basic
What identifier is guaranteed to not occur in $E_{s(e)}^x$?
What identifier is guaranteed to not occur freely in $E_{s(e)}^x$?
Back: $x$.
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707937867039-->
@ -595,7 +595,7 @@ END%%
%%ANKI
Basic
*Why* does $x$ not occur in $E_{s(e)}^x$?
*Why* does $x$ not occur freely in $E_{s(e)}^x$?
Back: Because $s(e)$ evaluates to a constant proposition.
Reference: Gries, David. *The Science of Programming*. Texts and Monographs in Computer Science. New York: Springer-Verlag, 1981.
<!--ID: 1707937867042-->

12
notes/logic/propositional.md
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@ -43,7 +43,7 @@ END%%
%%ANKI
Basic
What is an atomic statement?
Back: It cannot be broken up into smaller statements.
Back: One that cannot be broken up into smaller statements.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708199272087-->
END%%
@ -51,7 +51,7 @@ END%%
%%ANKI
Basic
What is a molecular statement?
Back: It can be broken up into smaller statements.
Back: One that can be broken up into smaller statements.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708199272091-->
END%%
@ -71,14 +71,6 @@ Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n
<!--ID: 1708199272099-->
END%%
%%ANKI
Basic
What distinguishes a sentence from a predicate?
Back: The latter is a sentence that contains free variables.
Reference: Oscar Levin, *Discrete Mathematics: An Open Introduction*, 3rd ed., n.d., [https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf](https://discrete.openmathbooks.org/pdfs/dmoi3-tablet.pdf).
<!--ID: 1708199272103-->
END%%
%%ANKI
Basic
What distinguishes a predicate from a statement?

41
notes/posix/signals.md
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@ -156,6 +156,47 @@ Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1706815743870-->
END%%
### SIGILL (4)
%%ANKI
Cloze
Signal {`SIGILL`} corresponds to number {4}.
Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1708812571645-->
END%%
%%ANKI
Basic
What is the `ILL` in `SIGILL` short for?
Back: **Ill**egal instruction
Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1708812571654-->
END%%
%%ANKI
Basic
When does a process receive a `SIGILL` signal?
Back: When the CPU encounters an instruction it can't run.
Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1708812571659-->
END%%
%%ANKI
Basic
Corruption of machine code would probably cause what signal raise?
Back: `SIGILL`
Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1708812571663-->
END%%
%%ANKI
Basic
Attempts to run a privileged instruction would probably cause what signal raise?
Back: `SIGILL`
Reference: Dowling, “A List of Signals and What They Mean.”
<!--ID: 1708812571668-->
END%%
## References
* Cooper, Mendel. “Advanced Bash-Scripting Guide,” n.d., 916.