part 1

Author: mflinn-broad

src/days/day6.rs

@@ -0,0 +1,37 @@
+use std::thread::current;
+
+use crate::util;
+
+pub fn run() {
+    let raw_input = util::read_input("inputs/day6.txt").unwrap();
+    let starting_statte = process(&raw_input);
+    println!("{:?}", starting_statte);
+    println!("Part 1: {:?}", part_1(starting_statte));
+
+}
+
+fn process(input: &str) -> [u64; 9] {
+    let mut tracker: [u64; 9] = [0; 9]; 
+    input.trim().split(',')
+        .map(|day_str| day_str.parse::<u64>().unwrap())
+        .for_each(|day| tracker[day as usize] += 1);
+    tracker
+}
+
+fn part_1(state: [u64; 9]) -> usize {
+    let final_state: [u64; 9] = (1..=80)
+        .fold(state, |mut curr_state, _| {
+            let mut temp_state: [u64; 9] = [0; 9];
+            temp_state.copy_from_slice(&curr_state);
+
+            for bucket in 1..9 {
+                curr_state[bucket-1] = temp_state[bucket];
+            }
+
+            curr_state[6] += temp_state[0];
+            curr_state[8] = temp_state[0];
+            println!("{:?}", curr_state);
+            curr_state
+        });
+    final_state.iter().map(|count| *count as usize).sum()
+}

src/days/mod.rs

@@ -3,3 +3,4 @@ pub mod day2;
 pub mod day3;
 pub mod day4;
 pub mod day5;
+pub mod day6;

src/main.rs

@@ -11,4 +11,6 @@ fn main() {
     day4::run();
     println!("Day 5 --------");
     day5::run();
+    println!("Day 6 --------");
+    day6::run();
 }