Added 2022, first few problems

3 files changed, 62 insertions, 0 deletions

diff --git a/2022/03/a.rs b/2022/03/a.rs
new file mode 100644
index 0000000..568546c
--- /dev/null
+++ b/2022/03/a.rs
@@ -0,0 +1,26 @@
+mod common;
+use common::*;
+
+fn get_rep_val(rucksack: &[u8]) -> i64 {
+    let mut seen = [false; 256];
+    let mid = rucksack.len()/2;
+    for i in 0..mid {
+        seen[rucksack[i] as usize] = true;
+    }
+    for i in mid..rucksack.len() {
+        if seen[rucksack[i] as usize] {
+            return value(rucksack[i] as char);
+        }
+    }
+    panic!("Could not find repeated char");
+}
+
+fn main() {
+    let mut sum = 0;
+    let mut line = String::new();
+    while std::io::stdin().read_line(&mut line).unwrap() > 0 {
+        sum += get_rep_val(line.as_bytes());
+        line.clear();
+    }
+    println!("{sum}");
+}
diff --git a/2022/03/b.rs b/2022/03/b.rs
new file mode 100644
index 0000000..89da764
--- /dev/null
+++ b/2022/03/b.rs
@@ -0,0 +1,29 @@
+mod common;
+use common::*;
+
+fn get_rep_val(e: &[String; 3]) -> i64 {
+    let mut seen = [[false; 256]; 2];
+    for i in 0..2 {
+        for c in e[i].chars() {
+            seen[i][c as usize] = true;
+        }
+    }
+    for c in e[2].chars() {
+        if seen[0][c as usize] && seen[1][c as usize] {
+            return value(c);
+        }
+    }
+    panic!("Could not find repeated char");
+}
+
+fn main() {
+    let mut sum = 0;
+    let mut lines: [String; 3] = Default::default();
+    while std::io::stdin().read_line(&mut lines[0]).unwrap() > 0 {
+        let _ = std::io::stdin().read_line(&mut lines[1]);
+        let _ = std::io::stdin().read_line(&mut lines[2]);
+        sum += get_rep_val(&lines);
+        for l in &mut lines { l.clear(); }
+    }
+    println!("{sum}");
+}
diff --git a/2022/03/common.rs b/2022/03/common.rs
new file mode 100644
index 0000000..cf323f5
--- /dev/null
+++ b/2022/03/common.rs
@@ -0,0 +1,7 @@
+pub fn value(c: char) -> i64 {
+    match c {
+        'a'..='z' => (c as i64) - ('a' as i64) + 1,
+        'A'..='Z' => (c as i64) - ('A' as i64) + 27,
+        _ => panic!("Error: unexpected character '{}'", c)
+    }
+}