day 2: reports problem dampener (wrong)

src/advent_of_code/mon_02.rs

@@ -9,36 +9,12 @@ pub fn check_reports_safety(input: &str) -> ReportSafety {
 
     // 1. All levels must be all increasing or decreasing
     // 2. All levels must change by at leat one and at most three
-
     for report in report_list {
         if report.len() < 2 {
-            safe_count += 1;
             break;
         }
 
-        let mut safe = true;
-        let initial_direction: ReportDirection = get_report_direction(&report[0..=1]);
-        let mut problems_damped_count = 0;
-
-        'report_check: for index in 1..report.len() {
-            let prev = index - 1;
-            let distance = calc_distance(report[index], report[prev]);
-            let direction = get_report_direction(&[report[prev], report[index]]);
-
-            if report[index] == report[prev]
-                || distance < 1
-                || distance > 3
-                || direction != initial_direction
-            {
-                if report_problem_dampener(&report) == false {
-                    safe = false;
-                    break 'report_check;
-                }
-                problems_damped_count += 1;
-            }
-        }
-
-        if safe {
+        if is_report_safe(&report, true) {
             safe_count += 1;
         }
     }
@@ -46,11 +22,45 @@ pub fn check_reports_safety(input: &str) -> ReportSafety {
     safe_count
 }
 
-// NOTE: the simples solition is by brute force...
-fn report_problem_dampener(report: &Vec<Report>) -> bool {}
+fn is_report_safe(report: &Report, apply_problem_dampener: bool) -> bool {
+    if report.len() < 2 {
+        return false;
+    }
+    let mut safe = true;
+    let initial_direction: ReportDirection = get_report_direction(&report[0..=1]);
+
+    'report_check: for index in 1..report.len() {
+        if !is_level_pair_valid(&report[index - 1], &report[index], &initial_direction) {
+            if apply_problem_dampener {
+                let sliced_index_report =
+                    [&report[0..index], &report[index + 1..report.len()]].concat();
+                if is_report_safe(&sliced_index_report, false) {
+                    break 'report_check;
+                } else {
+                    let sliced_prev_report =
+                        [&report[0..index - 1], &report[index..report.len()]].concat();
+                    if is_report_safe(&sliced_prev_report, false) {
+                        break 'report_check;
+                    }
+                }
+            }
+            safe = false;
+            break 'report_check;
+        }
+    }
+
+    safe
+}
+
+fn is_level_pair_valid(first: &Level, second: &Level, initial_direction: &ReportDirection) -> bool {
+    let distance = calc_distance(*second, *first);
+    let direction = get_report_direction(&[*first, *second]);
+
+    !(first == second || distance < 1 || distance > 3 || direction != *initial_direction)
+}
 
 // FIXME: this is not a good function, since may try to access an invalid index
-fn get_report_direction(report: &[Report]) -> ReportDirection {
+fn get_report_direction(report: &[Level]) -> ReportDirection {
     if report[1] - report[0] > 0 {
         ReportDirection::Increasing
     } else {

src/advent_of_code/types.rs

@@ -2,7 +2,8 @@ pub type Id = i32;
 pub type Key = Id;
 pub type Similarity = Id;
 
-pub type Report = i32;
+pub type Level = i32;
+pub type Report = Vec<Level>;
 pub type ReportSafety = u32;
 
 #[derive(Debug, PartialEq, Eq)]

src/advent_of_code/utils.rs

@@ -17,14 +17,14 @@ pub fn read_id_lists(input: &str) -> (Vec<Id>, Vec<Id>) {
     return (list_1, list_2);
 }
 
-pub fn read_report_list(input: &str) -> Vec<Vec<Report>> {
-    let mut report_list: Vec<Vec<Report>> = vec![];
+pub fn read_report_list(input: &str) -> Vec<Report> {
+    let mut report_list: Vec<Report> = vec![];
 
     for report in read_to_string(input).unwrap().lines() {
         let level_list = report.split(" ");
-        let mut report_vec: Vec<Report> = vec![];
+        let mut report_vec: Report = vec![];
         for level in level_list {
-            report_vec.push(level.parse::<Report>().unwrap());
+            report_vec.push(level.parse::<Level>().unwrap());
         }
         report_list.push(report_vec);
     }