day7

3 files changed, 132 insertions, 2 deletions

diff --git a/src/day7pt1.rs b/src/day7pt1.rs
new file mode 100644
index 0000000..064b622
--- /dev/null
+++ b/src/day7pt1.rs
@@ -0,0 +1,60 @@
+use std::cmp::Ordering;
+
+pub fn cmp_hands(a: &str, b: &str) -> Ordering {
+    let s = String::from("AKQJT98765432");
+    // first rule
+    let mut cnt_a = vec![];
+    let mut cnt_b = vec![];
+    for c in s.chars() {
+        cnt_a.push(a.match_indices(c).count());
+        cnt_b.push(b.match_indices(c).count());
+    }
+    cnt_a.sort();
+    cnt_a.reverse();
+    cnt_b.sort();
+    cnt_b.reverse();
+    for i in 0..cnt_a.len() {
+        if cnt_a[i] != cnt_b[i] {
+            if (cnt_a[i] as i64 - cnt_b[i] as i64) < 0 {
+                return Ordering::Less;
+            } else {
+                return Ordering::Greater;
+            }
+        }
+    }
+
+    // second rule
+    for i in 0..a.len() {
+        let ac = a.chars().nth(i).unwrap();
+        let bc = b.chars().nth(i).unwrap();
+        if ac != bc {
+            let a_i = s.chars().position(|x| x == ac).unwrap();
+            let b_i = s.chars().position(|x| x == bc).unwrap();
+
+            if (b_i as i64 - a_i as i64) < 0 {
+                return Ordering::Less;
+            } else {
+                return Ordering::Greater;
+            }
+        }
+    }
+
+    return Ordering::Equal;
+}
+
+pub fn main() {
+    let txt = std::fs::read_to_string("./input/day7.txt").unwrap();
+    let mut hands = vec![];
+    for line in txt.lines() {
+        let x = line.split(" ").collect::<Vec<_>>();
+        hands.push((x[0], x[1].parse::<u64>().unwrap()));
+    }
+
+    hands.sort_by(|a, b| cmp_hands(a.0, b.0));
+
+    let mut sum = 0;
+    for i in 0..hands.len() {
+        sum += hands[i].1 * (i + 1) as u64;
+    }
+    println!("{}", sum);
+}
diff --git a/src/day7pt2.rs b/src/day7pt2.rs
new file mode 100644
index 0000000..b536cac
--- /dev/null
+++ b/src/day7pt2.rs
@@ -0,0 +1,68 @@
+use std::cmp::Ordering;
+
+pub fn cmp_hands(a: &str, b: &str) -> Ordering {
+    let s1 = String::from("AKQT98765432");
+    // first rule
+    let mut cnt_a = vec![];
+    let mut cnt_b = vec![];
+    for c in s1.chars() {
+        cnt_a.push(a.match_indices(c).count());
+        cnt_b.push(b.match_indices(c).count());
+    }
+
+    let a_jok = a.match_indices("J").count();
+    let b_jok = b.match_indices("J").count();
+
+    cnt_a.sort();
+    cnt_a.reverse();
+    cnt_b.sort();
+    cnt_b.reverse();
+    cnt_a[0] += a_jok;
+    cnt_b[0] += b_jok;
+
+    for i in 0..cnt_a.len() {
+        if cnt_a[i] != cnt_b[i] {
+            if (cnt_a[i] as i64 - cnt_b[i] as i64) < 0 {
+                return Ordering::Less;
+            } else {
+                return Ordering::Greater;
+            }
+        }
+    }
+
+    let s2 = String::from("AKQT98765432J");
+    // second rule
+    for i in 0..a.len() {
+        let ac = a.chars().nth(i).unwrap();
+        let bc = b.chars().nth(i).unwrap();
+        if ac != bc {
+            let a_i = s2.chars().position(|x| x == ac).unwrap();
+            let b_i = s2.chars().position(|x| x == bc).unwrap();
+
+            if (b_i as i64 - a_i as i64) < 0 {
+                return Ordering::Less;
+            } else {
+                return Ordering::Greater;
+            }
+        }
+    }
+
+    return Ordering::Equal;
+}
+
+pub fn main() {
+    let txt = std::fs::read_to_string("./input/day7.txt").unwrap();
+    let mut hands = vec![];
+    for line in txt.lines() {
+        let x = line.split(" ").collect::<Vec<_>>();
+        hands.push((x[0], x[1].parse::<u64>().unwrap()));
+    }
+
+    hands.sort_by(|a, b| cmp_hands(a.0, b.0));
+
+    let mut sum = 0;
+    for i in 0..hands.len() {
+        sum += hands[i].1 * (i + 1) as u64;
+    }
+    println!("{}", sum);
+}
diff --git a/src/main.rs b/src/main.rs
index 1eae0ee..dfe1351 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,7 @@
-mod day6pt2;
+mod day7pt1;
+mod day7pt2;
 
 fn main() {
-    day6pt2::main();
+    day7pt1::main();
+    day7pt2::main();
 }