Add day 01

data/examples/01.txt

@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3

src/bin/01.rs

@@ -1,11 +1,80 @@
+use std::collections::HashMap;
+
 advent_of_code::solution!(1);
 
 pub fn part_one(input: &str) -> Option<u32> {
-    None
+    // println!("{}", input);
+    let mut column1 = Vec::new();
+    let mut column2 = Vec::new();
+
+    for line in input.lines(){
+        // let line = line?;
+        let numbers: Vec<i32> = line
+            .split_whitespace()
+            .filter_map(|s| s.parse().ok())
+            .collect();
+
+        if numbers.len() == 2 { // Ensure we have two numbers
+            column1.push(numbers[0].clone());
+            column2.push(numbers[1].clone());
+        }
+    }
+    println!("{:?}", column1);
+    println!("{:?}", column2);
+
+    column1.sort();//sort_by(|a, b| a.cmp(b));
+    column2.sort();// (|a, b| a.cmp(b));
+
+    // let result:i32 = column1.iter()
+    //     .zip(column1.iter())
+    //     .map(|(&left, &right)| (left - right).abs())
+    //     .sum();
+    let mut result: i32 = 0;
+    for i in 0..column1.len() {
+        let left = column1[i];
+        let right = column2[i];
+        result += (left - right).abs();
+    }
+
+    Some(result as u32)
 }
 
 pub fn part_two(input: &str) -> Option<u32> {
-    None
+    let mut column1 = Vec::new();
+    let mut column2 = Vec::new();
+
+    for line in input.lines(){
+        // let line = line?;
+        let numbers: Vec<i32> = line
+            .split_whitespace()
+            .filter_map(|s| s.parse().ok())
+            .collect();
+
+        if numbers.len() == 2 {
+            column1.push(numbers[0].clone());
+            column2.push(numbers[1].clone());
+        }
+    }
+    // println!("{:?}", column1);
+    // println!("{:?}", column2);
+
+    column1.sort();
+    column2.sort();
+
+    let mut count_map = HashMap::new();
+    for &num in &column2 {
+        *count_map.entry(num).or_insert(0) += 1;
+    }
+
+    let mut result: i32 = 0;
+    for i in 0..column1.len() {
+        let left = column1[i];
+
+        let count = count_map.get(&left).unwrap_or(&0);
+        result += left *count;
+    }
+
+    Some(result as u32)
 }
 
 #[cfg(test)]
@@ -15,12 +84,12 @@ mod tests {
     #[test]
     fn test_part_one() {
         let result = part_one(&advent_of_code::template::read_file("examples", DAY));
-        assert_eq!(result, None);
+        assert_eq!(result, Some(11));
     }
 
     #[test]
     fn test_part_two() {
         let result = part_two(&advent_of_code::template::read_file("examples", DAY));
-        assert_eq!(result, None);
+        assert_eq!(result, Some(31));
     }
 }