day_10: part 2 done

src/advent_of_code/mod.rs

@@ -78,6 +78,8 @@ pub fn historian_hysteria() {
     // println!("The disk checksum is {}", disk_checksum);
 
     // Tuesday 10
-    let trailhead_score = tue_10::hoof_it("./assets/day_10_trail_map_input");
+    let (trailhead_score, full_trailhead_score) =
+        tue_10::hoof_it("./assets/day_10_trail_map_input");
     println!("The trail head sum score is {}", trailhead_score);
+    println!("The full trail head sum score is {}", full_trailhead_score);
 }

src/advent_of_code/tue_10.rs

@@ -2,10 +2,10 @@ use utils::read_trail_map_input;
 
 use super::*;
 
-pub fn hoof_it(input: &str) -> usize {
+pub fn hoof_it(input: &str) -> (usize, usize) {
     let trail_map = read_trail_map_input(input);
 
-    let vector_of_scores = explore_map(trail_map);
+    let (vector_of_scores, vector_of_all_scores) = explore_map(trail_map);
 
     let mut sum_of_scores: usize = 0;
 
@@ -14,22 +14,29 @@ pub fn hoof_it(input: &str) -> usize {
         sum_of_scores += score;
     }
 
-    sum_of_scores
+    let mut sum_of_all_scores: usize = 0;
+    for score in vector_of_all_scores {
+        sum_of_all_scores += score;
+    }
+
+    (sum_of_scores, sum_of_all_scores)
 }
 
-pub fn explore_map(map: TrailMap) -> Vec<TrailScore> {
+pub fn explore_map(map: TrailMap) -> (Vec<TrailScore>, Vec<TrailScore>) {
     let mut trail_score_list: Vec<TrailScore> = vec![];
+    let mut full_trail_score_list: Vec<TrailScore> = vec![];
 
     for y_index in 0..map.len() {
         for x_index in 0..map[y_index].len() {
             if map[y_index][x_index] == 0 {
                 let mut reached_ends: Vec<(usize, usize)> = vec![];
                 trail_score_list.push(explore_position(x_index, y_index, &map, &mut reached_ends));
+                full_trail_score_list.push(explore_all_positions(x_index, y_index, &map));
             }
         }
     }
 
-    trail_score_list
+    (trail_score_list, full_trail_score_list)
 }
 
 pub fn explore_position(
@@ -55,6 +62,21 @@ pub fn explore_position(
     score_sum
 }
 
+pub fn explore_all_positions(x: TrailPosition, y: TrailPosition, map: &TrailMap) -> usize {
+    if map[y][x] == 9 {
+        return 1;
+    }
+
+    let mut score_sum: usize = 0;
+    for next_position in get_pos_surroundings(x, y, map) {
+        if map[next_position.1][next_position.0] == map[y][x] + 1 {
+            score_sum += explore_all_positions(next_position.0, next_position.1, map);
+        }
+    }
+
+    score_sum
+}
+
 pub fn get_pos_surroundings(
     x: TrailPosition,
     y: TrailPosition,