Updates

december_14/src/main.rs

@@ -0,0 +1,66 @@
+use std::collections::BTreeMap;
+use std::fs::File;
+use std::io::{BufReader};
+use std::io::prelude::*;
+
+const STEPS: u32 = 40;
+
+fn main(){
+    let file = File::open("./input.txt").expect("Read failed");
+    let reader = BufReader::new(file);
+
+    let mut line_vec = Vec::new();
+
+    for line in reader.lines() {
+        line_vec.push(line.unwrap());
+    }
+
+    let mut input_seq: Vec<char> = line_vec[0].chars().collect();
+    let mut rules: Vec<( (char, char) , char )> = Vec::new();
+
+    for i in 2..line_vec.len() {
+        let split_vec: Vec<&str> = line_vec[i].split(" -> ").collect();
+        let input_vec: Vec<char> = split_vec[0].to_owned().chars().collect();
+        let input_tuple = (input_vec[0], input_vec[1]);
+
+        let output = split_vec[1].chars().collect::<Vec<char>>()[0];
+
+        rules.push( ( input_tuple, output  ) );
+    }
+
+    for step in 0..STEPS {
+        let mut output_seq: Vec<char> = Vec::new();
+        for i in 0..input_seq.len() - 1 {
+            let first = input_seq[i];
+            let second = input_seq[i + 1];
+    
+            output_seq.push(first);
+            for rule in &rules {
+                let r_in = rule.0;
+                let r_out = rule.1;
+                if first == r_in.0 && second == r_in.1 {
+                    output_seq.push(r_out);
+                    break;
+                }
+            }
+            
+        }
+        output_seq.push(input_seq[input_seq.len()-1]);
+    
+        println!("Step: {}", step);
+        input_seq = output_seq;
+    }
+
+    let mut counts = BTreeMap::new();
+    for word in input_seq.iter() {
+        *counts.entry(word).or_insert(0) += 1;
+    }
+
+    let max = counts.iter().max_by_key(|&(_, count)| count);
+    let min = counts.iter().min_by_key(|&(_, count)| count);
+
+    println!("Max: {:?}, Min: {:?}, Diff: {}", min.unwrap(), max.unwrap(), max.unwrap().1 - min.unwrap().1) ;
+    
+    
+
+}