day08: rust

01/README.md

@@ -1,14 +1,16 @@
-# [Day 1](https://adventofcode.com/2022/day/1) 
+# [Day 1](https://adventofcode.com/2023/day/1) 
 :gift:
 
 Today's language: **Python**
+Execution time: **0,021 s**
 
 Both tasks are solved in one hell of a oneliner each:
+
 - Task 1: 153 characters / line
 - Task 2: 363 characters / line
 
-<!-- one-liners -->
 
 ```shell
-p day01.py
+python3 day01.py
 ```
+<!-- one-liners -->

02/README.md

@@ -2,12 +2,12 @@
 :gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,002 s**
 
 My very first rust program!
 
-<!-- my very first rust program -->
-
 ```shell
 rustc day02.rs
 ./day02
 ```
+<!-- my very first rust program -->

03/README.md

@@ -2,6 +2,7 @@
 :gift::gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,006 s**
 
 ```shell
 rustc day03.rs

04/README.md

@@ -2,6 +2,7 @@
 :gift::gift::gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,004 s**
 
 ```shell
 rustc day04.rs

05/README.md

@@ -2,12 +2,12 @@
 :gift::gift::gift::gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,009 s**
 
-Super fast, it runs both tasks in 0,002s on my pc.
-
-<!-- very efficient -->
+Super fast!
 
 ```shell
 rustc day05.rs
 ./day05
 ```
+<!-- very efficient -->

06/README.md

@@ -2,12 +2,12 @@
 :gift::gift::gift::gift::gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,001 s**
 
 *Midnight formula go brrrrr*
 
-<!-- quadratic formula go *brrrr* -->
-
 ```shell
 rustc day06.rs
 ./day06
 ```
+<!-- quadratic formula go *brrr* -->

07/README.md

@@ -2,6 +2,7 @@
 :gift::gift::gift::gift::gift::gift::gift:
 
 Today's language: **Rust**
+Execution time: **0,007 s**
 
 Not pretty, but pretty fast.
 
@@ -9,4 +10,4 @@ Not pretty, but pretty fast.
 rustc day07.rs
 ./day07
 ```
-<!-- -->
+<!-- not pretty, but pretty fast -->

08/README.md

@@ -0,0 +1,12 @@
+# [Day 8](https://adventofcode.com/2023/day/8) 
+:gift::gift::gift::gift::gift::gift::gift::gift:
+
+Today's language: **Rust**
+Execution time: **0,039 s**
+
+Next time, I should just use 64 bit right from the start...
+
+```shell
+rustc day08.rs
+./day08
+```

08/day08.rs

@@ -0,0 +1,114 @@
+use std::io::{self, BufRead};
+use std::collections::HashMap;
+
+struct Junction(u32, u32);
+
+fn hash(s: &str) -> u32 {
+    let mut h: u32 = 0;
+    for (i, c) in s.as_bytes().iter().enumerate() {
+        h |= (*c as u32) << (8 * i);
+        // println!("i: {}, s={}, Char: {:8b}, h: {:32b}", i, s, c, h);
+    }
+    return h;
+}
+
+fn ends_with(h: &u32, c: char) -> bool {
+    return (h >> (8 * 2)) == (c as u32);
+}
+
+fn gcd(mut x: u64, mut y: u64) -> u64 {
+    let mut d: u64;
+    assert!(x != 0 && y != 0);
+    while y != 0 {
+        d = y;
+        y = x % y;
+        x = d;
+    }
+    return x
+}
+
+fn lcm(a: u64, b: u64) -> u64 {
+    return (a * b) / gcd(a, b);
+}
+
+fn main() {
+    let input = "input.txt";
+    // let input = "example.txt";
+    let mut lines = read_lines(&input);
+    let Ok(instructions) = lines.next().expect("No line found") else { panic!("No line found") };
+    lines.next();
+    let mut junctions = HashMap::new();
+    let mut junctions_a = Vec::new();
+    for line in lines.map(|r| r.ok().unwrap()) {
+        let junction = hash(&line[0..3]);
+        junctions.insert(junction, Junction(hash(&line[7..10]), hash(&line[12..15])));
+        if ends_with(&junction, 'A') {
+            junctions_a.push(junction);
+        }
+    }
+    let match_junction = |junction: &u32, instruction: &char| -> u32 {
+        match instruction {
+            'R' => junctions[&junction].1,
+            'L' => junctions[&junction].0,
+            _ => panic!("Unknown instruction {}", instruction),
+        }
+    };
+    // task 1
+    let mut steps: u32 = 0;
+    let target = hash("ZZZ");
+    let mut junction = hash("AAA");
+    println!("Check endswidth {} {} {} {}", ends_with(&hash("AAA"), 'A'), ends_with(&hash("BFZ"), 'Z'), ends_with(&hash("AVD"), 'A'), ends_with(&hash("ZZS"), 'Z'));
+    'outer: loop {
+        for instruction in instructions.chars() {
+            if junction == target { break 'outer; }
+            steps += 1;
+            junction = match_junction(&junction, &instruction);
+        }
+    }
+    println!("Required steps(1): {}", steps);
+    let mut steps_to_z = vec![0 as u32; junctions_a.len()];
+    let mut steps_cycle = vec![0 as u32; junctions_a.len()];
+    let mut first_z = vec![0 as u32; junctions_a.len()];
+    for i in 0..junctions_a.len() {
+        steps = 0;
+        'outer: loop {
+            for instruction in instructions.chars() {
+                if ends_with(&junctions_a[i], 'Z') {
+                    if steps_to_z[i] == 0 {
+                        steps_to_z[i] = steps;
+                        first_z[i] = junctions_a[i];
+                        steps = 0;
+                    }
+                    else {
+                        assert_eq!(first_z[i], junctions_a[i], "Z->Z is not a cycle!");
+                        steps_cycle[i] = steps;
+                        break 'outer;
+                    }
+                }
+                // print!("Step {:012}: junction[{}]={:024b}\r", steps, i, junctions_a[i]);
+                junctions_a[i] = match_junction(&junctions_a[i], &instruction);
+                steps += 1;
+            }
+        }
+    }
+    for i in 0..junctions_a.len() {
+        println!("A-Z: {}, Z->Z: {}", steps_to_z[i], steps_cycle[i]);
+    }
+    let mut steps: u64 = steps_cycle[0] as u64;
+    for i in 1..steps_cycle.len() {
+        print!("lcm({:12}, {:8})", steps, steps_cycle[i]);
+        steps = lcm(steps, steps_cycle[i] as u64);
+        println!("={}", steps);
+    }
+    println!("Required steps(2): {}", steps);
+
+}
+
+
+fn read_lines<P>(filename: P) -> io::Lines<io::BufReader<std::fs::File>>
+where P: AsRef<std::path::Path>, {
+    return match std::fs::File::open(filename) {
+        Err(why) => panic!("Could not open file. {}", why),
+        Ok(file) => std::io::BufReader::new(file).lines()
+    };
+}

README.md

@@ -2,11 +2,13 @@
 This is a repository for my solutions for the [advent of code 2023](https://adventofcode.com/2023).
 
 <!-- table begin -->
-| Day      | Language | Execuction time | Comment                      |
-|:---:     |:---:     | ---:            | ---                          |
-| [01](01) | Python   | 0,015 s         | one-liners                   |
-| [02](02) | Rust     | 0,001 s         | my very first rust program   |
-| [03](03) | Rust     | 0,001 s         |                              |
-| [04](04) | Rust     | 0,001 s         |                              |
-| [05](05) | Rust     | 0,001 s         | very efficient               |
-| [06](06) | Rust     | 0,001 s         | quadratic formula go *brrrr* |
+| Day      | Language | Execuction time | Comment                     |
+|:---:     |:---:     | ---:            | ---                         |
+| [01](01) | Python   | 0,021 s         | one-liners                  |
+| [02](02) | Rust     | 0,002 s         | my very first rust program  |
+| [03](03) | Rust     | 0,006 s         |                             |
+| [04](04) | Rust     | 0,004 s         |                             |
+| [05](05) | Rust     | 0,009 s         | very efficient              |
+| [06](06) | Rust     | 0,001 s         | quadratic formula go *brrr* |
+| [07](07) | Rust     | 0,007 s         | not pretty, but pretty fast |
+| [08](08) | Rust     | 0,039 s         |                             |

README.md.temp

@@ -1,9 +1,10 @@
-# [Day X](https://adventofcode.com/2023/day/X) 
+# [Day DAY](https://adventofcode.com/2023/day/DAY) 
 :gift:
 
-Today's language: **Y**
+Today's language: **LANG**
+Execution time: **EXECTIME**
 
 ```shell
-
+HOWTORUN
 ```
-<!-- -->
+<!-- COMMENT -->

make_day_readme.sh

@@ -0,0 +1,89 @@
+#!/bin/bash
+# pass comment as param $1 and select day with day=X ./make_day_readme.sh
+maxday=$(ls -d */ | sed -r 's|0*(.*)/|\1|g' | tail -1)
+[[ -z $day ]] && day=$maxday
+day_dir=$(printf "%02d" $day)
+readme=$day_dir/README.md
+
+FMT_VAR='\e[32m%s: \e[0m%s\n'
+FMT_ERR='\e[31m%s\e[0m\n'
+FMT_WARN='\e[33m%s\e[0m\n'
+
+echo Making Readme of day $day in $readme
+
+function find_lang {
+    # 1: fileext, 2: lang, 3: howto
+    sourcefile=$(ls $day_dir/*.$1 2> /dev/null)
+    [[ $? != 0 ]] && return
+    sourcefile=$(basename $sourcefile)
+    printf "$FMT_VAR" "Determined Langugae" "$2 ($sourcefile)"
+    sed -i "s/LANG/$2/" $readme
+    howto=$(echo "$3" | sed "s|SOURCE|$sourcefile|")
+    sed -i "s(HOWTORUN($howto(" $readme
+}
+
+function get_time {
+    cd $day_dir
+    exe=$(find . -type f -executable)
+    exe=$(basename $exe)
+    if [[ $(echo $exe | wc -w) != 1 ]]; then
+        printf "$FMT_ERR" "Found multiple or no executables for day $day: '$exe'"
+        return 1
+        time=Error
+    else
+        time=$({ time ./$exe; } 2>&1)
+        if [[ $? != 0 ]]; then
+            printf "$FMT_ERR" "Execution error in './$exe' in '$(pwd)'. Output:"
+            printf "\e[34m"
+            echo -e "$time"
+            printf "\e[0m"
+            return 1
+        fi
+        time=$(echo -e "$time" | tail -3 | head -1 | awk '{print $2}')
+        re='([[:digit:]]+)m([[:digit:]]+),([[:digit:]]+)s'
+        [[ $time =~ $re ]]
+        min=${BASH_REMATCH[1]}
+        sec=${BASH_REMATCH[2]}
+        msec=${BASH_REMATCH[3]}
+        if [[ $min != 0 ]]; then
+            time="$min m $sec,$msec s"
+        else
+            time="$sec,$msec s"
+        fi
+        # elif [[ $sec != 0 ]]; then
+        #     time="$sec,$msec s"
+        # else
+        #     time="$((msec+0)) ms"
+        # fi
+    fi
+}
+
+
+
+gifts=""
+for i in $(seq $day); do gifts+=":gift:"; done
+sed "s/DAY/$day/g" README.md.temp | sed "s/:gift:/$gifts/" > $day_dir/README.md
+get_time
+if [[ $? == 0 ]]; then
+    cd ..
+    printf "$FMT_VAR" "exectime" "$time"
+    sed -i "s/EXECTIME/$time/" $readme
+else
+    cd ..
+    printf "$FMT_WARN" "No execution time determined"
+    sed -i '/.*EXECTIME.*/d' $readme
+fi
+
+
+
+if [[ -z $1 ]]; then
+    printf "$FMT_WARN" "No comment provided"
+    sed -i "/<!-- COMMENT -->/d" $readme
+else
+    printf "$FMT_VAR" "Comment" "'$1'"
+    sed -i "s|COMMENT|$1|" $readme
+fi
+
+find_lang py Python "python3 SOURCE"
+find_lang rs Rust "rustc SOURCE\n./day${day_dir}"
+find_lang cpp C++ "g++ SOURCE -o day${day_dir}\n ./day${day_dir}"

make_readme.sh

@@ -1,38 +1,14 @@
 #!/bin/bash
 
-
-
 table="| Day | Language | Execuction time | Comment |\n"
 table+="|:---:|:---:| ---:| --- |\n"
 for day in $(seq -f "%02g" 1 25); do
     [[ ! -d "$day" ]] && continue
     # echo $day
-    lang=$(grep -E "Today's language: "'\*\*[a-zA-Z0-9_]+\*\*' $day/README.md | sed -r 's/.*\*\*(.+)\*\*.*/\1/')
-    exe=$(find $day -type f -executable)
-    if [[ $(echo $exe | wc -w) != 1 ]]; then
-        echo "Found multiple or no executables for day $day: '$exe'"
-        time=Error
-    else
-        time=$({ time ./$exe; } 2>&1 | tail -3 | head -1 | awk '{print $2}')
-        re='([[:digit:]]+)m([[:digit:]]+),([[:digit:]]+)s'
-        [[ $time =~ $re ]]
-        min=${BASH_REMATCH[1]}
-        sec=${BASH_REMATCH[2]}
-        msec=${BASH_REMATCH[3]}
-        if [[ $min != 0 ]]; then
-            time="$min m $sec,$msec s"
-        else
-            time="$sec,$msec s"
-        fi
-        # elif [[ $sec != 0 ]]; then
-        #     time="$sec,$msec s"
-        # else
-        #     time="$((msec+0)) ms"
-        # fi
-    fi
+    lang=$(grep -E "Today's language:" $day/README.md | sed -r 's/.*\*\*(.+)\*\*.*/\1/')
+    exectime=$(grep -E "Execution time:" $day/README.md | sed -r 's/.*\*\*(.+)\*\*.*/\1/')
     comment=$(grep -E "<!-- .* -->" $day/README.md | head -1 | sed -r 's/.*<!-- *(.*) *-->.*/\1/')
-    table+="| [$day]($day) | $lang | $time | $comment |\n"
-    
+    table+="| [$day]($day) | $lang | $exectime | $comment |\n"
 done
 # remove table from readme
 sed -i '/<!-- table begin -->/q' README.md