day7 past1

day07/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day07"
+version = "0.1.0"

day07/Cargo.toml

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+[package]
+name = "day07"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

day07/src/main.rs

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+use std::{fs, collections::HashMap};
+
+fn main() {
+    let input = fs::read_to_string("input.txt").unwrap();
+    let mut input: Vec<_> = input.split('\n')
+        .map(|line| line.split(' ').collect::<Vec<_>>())
+        .collect();
+
+    for line in 0..input.len() {
+        let hand = input[line][0];
+        let mut card_freq: HashMap<char, i16> = HashMap::new();
+        for card in hand.chars() {
+            card_freq.entry(card)
+                .and_modify(|count| *count += 1)
+                .or_insert(1);
+        }
+
+        let mut set_count: HashMap<i16, i16> = HashMap::new();
+        for i in 1..=5 {
+            let card_count = card_freq.values().filter(|x| **x == i).count().try_into().unwrap();
+            if card_count != 0 {
+                set_count.insert(i, card_count);
+            }
+        }
+
+        let power = match set_count {
+            x if x.contains_key(&5) => "7",
+            x if x.contains_key(&4) => "6",
+            x if x.contains_key(&3) && x.contains_key(&2) => "5",
+            x if x.contains_key(&3) => "4",
+            x if x.get(&2).unwrap_or(&0) >= &2 => "3",
+            x if x.get(&2).unwrap_or(&0) == &1 => "2",
+            HashMap { .. } => "1"
+        };
+
+        input[line].push(power);
+    }
+
+    input.sort_by(|lhs, rhs| {
+        let lhs_power: i32 = lhs[2].parse().unwrap();
+        let rhs_power: i32 = rhs[2].parse().unwrap();
+        if lhs_power != rhs_power {
+            return lhs_power.cmp(&rhs_power);
+        }
+
+        let lhs_hand: Vec<i32> = lhs[0].chars().map(card_value).collect();
+        let rhs_hand: Vec<i32> = rhs[0].chars().map(card_value).collect();
+        for i in 0..5 {
+            if lhs_hand[i] == rhs_hand[i] { continue; }
+            return lhs_hand[i].cmp(&rhs_hand[i]);
+        }
+
+        panic!("Should not be reachable");
+    });
+
+
+    let mut total_winnings = 0;
+    for i in 0..input.len() {
+        let bid: usize = input[i][1].parse().unwrap();
+        total_winnings += (i + 1) * bid;
+    }
+
+    println!("{}", total_winnings);
+
+
+}
+
+
+fn card_value(card: char) -> i32 {
+    match card {
+        'A' => 13,
+        'K' => 12,
+        'Q' => 11,
+        'J' => 10,
+        'T' => 9,
+        '9' => 8,
+        '8' => 7,
+        '7' => 6,
+        '6' => 5,
+        '5' => 4,
+        '4' => 3,
+        '3' => 2,
+        '2' => 1,
+        _ => panic!("invalid card")
+    }
+}