moved code around so each year is a package.

2019/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name="aoc2019"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+core = { path = "../core" }

2019/src/bin/2019_01a.rs

@@ -0,0 +1,20 @@
+#![feature(int_roundings)]
+
+use core::read_data;
+
+fn fuel_calc(input: u32) -> u32 {
+    input.div_floor(3).saturating_sub(2)
+}
+
+fn main() {
+    let mut working_value = 0;
+    let binding = read_data("2019_01_data.txt");
+    let lines = binding.lines();
+    for line in lines {
+        let number: u32 = line.parse().unwrap();
+        // println!("Line -> {line} - [{number}]");
+        working_value += fuel_calc(number);
+    }
+    println!("Working Value without self-> {working_value}");
+}
+// 3228475

2019/src/bin/2019_01b.rs

@@ -0,0 +1,28 @@
+#![feature(int_roundings)]
+
+use core::read_data;
+
+fn fuel_calc(input: u32) -> u32 {
+    input.div_floor(3).saturating_sub(2)
+}
+
+fn total_fuel(mut mass: u32) -> u32 {
+    let mut total = 0;
+    while mass > 0 {
+        mass = fuel_calc(mass);
+        total += mass;
+    }
+    total
+}
+
+fn main() {
+    let mut working_value = 0;
+    let binding = read_data("2019_01_data.txt");
+    let lines = binding.lines();
+    for line in lines {
+        let number: u32 = line.parse().unwrap();
+        working_value += total_fuel(number);
+    }
+    println!("Working Value without self-> {working_value}");
+}
+// 4839845

2019/src/bin/2019_02a.rs

@@ -0,0 +1,9 @@
+use core::read_data;
+
+fn main() {
+    let directions = read_data("2019_02_data.txt").split(", ");
+
+    for direction in directions {
+
+    }
+}

2019/src/bin/2019_04a.rs

@@ -0,0 +1,35 @@
+fn is_valid(input: i32) -> bool {
+    let mut has_double = false;
+    let mut last_digit: Option<i32> = None;
+
+    for current_char in input.to_string().chars() {
+        let current_digit = current_char.to_digit(10).unwrap() as i32;
+
+        if let Some(last) = last_digit {
+            if last > current_digit {
+                // Digits decrease → invalid
+                return false;
+            }
+            if last == current_digit {
+                has_double = true;
+            }
+        }
+
+        last_digit = Some(current_digit);
+    }
+
+    has_double
+}
+
+fn main() {
+    for input in 136818..=685979 {
+        print!("START [[{input}]]");
+        if is_valid(input) {
+            println!("Success at {input}");
+            break;
+        }
+    }
+}
+// 136888 bad
+// 145678 bad
+// 136888

2019/src/bin/2019_04a_chatgpt.rs

@@ -0,0 +1,31 @@
+fn is_valid(input: i32) -> bool {
+    let mut has_double = false;
+    let mut last_digit: Option<i32> = None;
+
+    for current_char in input.to_string().chars() {
+        let current_digit = current_char.to_digit(10).unwrap() as i32;
+
+        if let Some(last) = last_digit {
+            if last > current_digit {
+                // Digits decrease → invalid
+                return false;
+            }
+            if last == current_digit {
+                has_double = true;
+            }
+        }
+
+        last_digit = Some(current_digit);
+    }
+
+    has_double
+}
+
+fn main() {
+    for input in 136818..=685979 {
+        if is_valid(input) {
+            println!("Success at {input}");
+            break;
+        }
+    }
+}