do day 8

2022/src/day_8.rs

@@ -0,0 +1,103 @@
+use std::collections::HashSet;
+
+type Data = Vec<Vec<i32>>;
+type Output = i32;
+fn parse(input: &str) -> Data {
+    input
+        .lines()
+        .map(|line| {
+            line.chars()
+                .map(|c| c.to_digit(10).unwrap() as i32)
+                .collect()
+        })
+        .collect()
+}
+fn part_one(data: Data) -> Output {
+    let mut visible = HashSet::<(usize, usize)>::new();
+    (0..data.len()).for_each(|i| {
+        let mut max = -1;
+        for j in 0..data[i].len() {
+            if data[i][j] > max {
+                max = data[i][j];
+                visible.insert((i, j));
+            }
+        }
+
+        let mut max = -1;
+        for j in (0..data[i].len()).rev() {
+            if data[i][j] > max {
+                max = data[i][j];
+                visible.insert((i, j));
+            }
+        }
+    });
+    for j in 0..data.len() {
+        let mut max = -1;
+        (0..data.len()).for_each(|i| {
+            if data[i][j] > max {
+                max = data[i][j];
+                visible.insert((i, j));
+            }
+        });
+
+        let mut max = -1;
+        for i in (0..data.len()).rev() {
+            let i = i as usize;
+            if data[i][j] > max {
+                max = data[i][j];
+                visible.insert((i, j));
+            }
+        }
+    }
+    visible.len() as i32
+}
+fn part_two(data: Data) -> Output {
+    let mut max_count = -1;
+    for (i, row) in data.iter().enumerate() {
+        for (j, height) in row.iter().enumerate() {
+            let mut down = 0;
+            for idx in i + 1..row.len() {
+                down += 1;
+                if data[idx][j] >= *height {
+                    break;
+                }
+            }
+
+            let mut up = 0;
+            for idx in (0..i).rev() {
+                up += 1;
+                if data[idx][j] >= *height {
+                    break;
+                }
+            }
+
+            let mut right = 0;
+            for j in j + 1..row.len() {
+                right += 1;
+                if data[i][j] >= *height {
+                    break;
+                }
+            }
+
+            let mut left = 0;
+            for j in (0..j).rev() {
+                left += 1;
+                if data[i][j] >= *height {
+                    break;
+                }
+            }
+
+            max_count = std::cmp::max(up * left * right * down, max_count);
+        }
+    }
+    max_count
+}
+
+advent_of_code_macro::generate_tests!(
+    day 8,
+    parse,
+    part_one,
+    part_two,
+    sample tests [21, 8],
+    star tests [1_719, 590_824]
+);

2022/src/lib.rs

@@ -6,3 +6,4 @@ mod day_4;
 mod day_5;
 mod day_6;
 mod day_7;
+mod day_8;