Day 8. So much easier than 7 whewwww

day8/src/main.rs

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+fn main() {
+    let contents = std::fs::read_to_string("data.txt").expect("Failed to read file");
+    let grid = contents // make it a grid of u32
+        .lines()
+        .map(|l| {
+            l.chars()
+                .map(|c| c.to_digit(10).unwrap())
+                .collect::<Vec<u32>>()
+        })
+        .collect::<Vec<Vec<u32>>>();
+
+    let height = grid.len();
+
+    let mut visible = 0;
+    let mut high_score = 0;
+
+    for (row, line) in grid.iter().enumerate() {
+        for (col, tree) in line.iter().enumerate() {
+            let width = line.len();
+
+            let north = (0..row).map(|r| grid[r][col]).rev().collect::<Vec<u32>>();
+            let south = (row + 1..height)
+                .map(|r| grid[r][col])
+                .collect::<Vec<u32>>();
+            let west = (0..col).map(|c| grid[row][c]).rev().collect::<Vec<u32>>();
+            let east = (col + 1..width).map(|c| grid[row][c]).collect::<Vec<u32>>();
+
+            let dirs = vec![north, south, west, east];
+
+            // Part 1
+            if row == 0 || col == 0 || row == height - 1 || col == width - 1 {
+                visible += 1; // if it is on the edge, it is visible
+            } else {
+                if dirs.iter().any(|dir| dir.iter().all(|t| tree > t)) {
+                    visible += 1;
+                }
+            }
+
+            // Part 2
+            let score = dirs.iter().fold(1, |acc, dir| {
+                let position = dir.into_iter().position(|x| tree <= x);
+                acc * match position {
+                    Some(x) => x + 1,
+                    None => dir.len(), // hit an edge. return the distance to the edge
+                }
+            });
+
+            if score > high_score {
+                high_score = score;
+            }
+        }
+    }
+
+    println!("Number Visible: {:?}", visible);
+    println!("Highest Score: {:?}", high_score);
+}