day 4 completed

2023/day4/src/main.rs

@@ -1,21 +1,22 @@
 use std::fs;
-
+use aochelpers;
 use regex::Regex;
+
 #[macro_use(c)]
 extern crate cute;
 
 fn main() {
-    /* battleplan
+    /* battleplan part 1
     1. create a list for all the cards
         1.1 parse input
             1.1.1split on '|' and parse via regex both parts or whole thing via regex
         1.2 build list
             1.2.1 each value of the list represents a card
             1.2.2 representation of a card = 2 lists, winning numbers, and drawn numbers
-        1.3 map the list to convert card info into the amount of points
-        1.4 sum the points*/
-
-    let content = fs::read_to_string("input").expect("Should have been able to read the file");
+    2. map the list to convert card info into the amount of points
+    3. sum the points
+    */
+    let content = fs::read_to_string("input").expect("Could not read the file");
     let lines_array = content.split("\n").collect::<Vec<_>>();
     let number_regex = Regex::new(r"\d+").unwrap();
     let mut all_cards: Vec<(Vec<i32>, Vec<i32>)> = Vec::new();
@@ -46,9 +47,31 @@ fn main() {
         .collect();
     let part1: i32 = part1_array
         .iter()
-        .map(|x| i32::pow(2, x.clone().len() as u32 -1))
+        .map(|x| i32::pow(2, x.clone().len() as u32 - 1))
         .collect::<Vec<i32>>()
         .iter()
         .sum();
     println!("Part 1: {part1}");
+
+    /*
+    battleplan part 2
+    1. get the intersection between similar numbers left and right
+    2. add the amount of current card to subsequent cards
+    3. sum the newly created list of amount of cards
+     */
+    let mut part2_array: Vec<i32> = c! [1, for _x in 0..all_cards.len()];
+    for (card_index, card) in all_cards.iter().enumerate() {
+        let similar_amount = card
+            .1
+            .clone()
+            .into_iter()
+            .filter(|y| card.0.contains(y))
+            .collect::<Vec<i32>>()
+            .len() as i32;
+        for i in 1..similar_amount+1 {
+            part2_array[i32::min(card_index as i32 + i, 189) as usize] += part2_array[card_index];
+        }
+    }
+    let part2 = part2_array.iter().sum::<i32>();
+    println!("Part 2: {part2}");
 }