solved 18 and 67

add .idea to .gitignore

src/bin/problem_18.rs

@@ -0,0 +1,61 @@
+use std::cmp::max;
+
+fn main() {
+    println!("{}", find_max_total(get_triangle()));
+}
+
+fn get_triangle() -> Vec<Vec<usize>> {
+    vec![
+       vec![75],
+       vec![95, 64],
+       vec![17, 47, 82],
+       vec![18, 35, 87, 10],
+       vec![20, 04, 82, 47, 65],
+       vec![19, 01, 23, 75, 03, 34],
+       vec![88, 02, 77, 73, 07, 63, 67],
+       vec![99, 65, 04, 28, 06, 16, 70, 92],
+       vec![41, 41, 26, 56, 83, 40, 80, 70, 33],
+       vec![41, 48, 72, 33, 47, 32, 37, 16, 94, 29],
+       vec![53, 71, 44, 65, 25, 43, 91, 52, 97, 51, 14],
+       vec![70, 11, 33, 28, 77, 73, 17, 78, 39, 68, 17, 57],
+       vec![91, 71, 52, 38, 17, 14, 91, 43, 58, 50, 27, 29, 48],
+       vec![63, 66, 04, 68, 89, 53, 67, 30, 73, 16, 69, 87, 40, 31],
+       vec![04, 62, 98, 27, 23, 09, 70, 98, 73, 93, 38, 53, 60, 04, 23],
+    ]
+}
+
+fn find_max_total(grid: Vec<Vec<usize>>) -> usize {
+    let triangle_height = grid.len();
+    let mut idx = triangle_height - 1;
+    let mut highest_sums = match grid.get(idx) {
+        Some(sums) => sums.to_vec(),
+        None => panic!("Impossible path: check grid")
+    };
+    while idx > 0 {
+        idx -= 1;
+        let line = grid.get(idx).unwrap();
+        let mut new_highest_sums = Vec::new();
+        for (pos, &num) in line.iter().enumerate() {
+            new_highest_sums.push(max(num + highest_sums[pos], num + highest_sums[pos+1]))
+        }
+        highest_sums = new_highest_sums;
+    }
+    highest_sums[0]
+}
+
+#[cfg(test)]
+mod test_18 {
+    use crate::find_max_total;
+
+    #[test]
+    fn test_find_max_total() {
+        let grid = vec![
+            vec![3],
+            vec![7, 4],
+            vec![2, 4, 6],
+            vec![8, 5, 9, 3],
+        ];
+        assert_eq!(23, find_max_total(grid));
+    }
+
+}

src/bin/problem_67.rs

@@ -0,0 +1,55 @@
+use std::cmp::max;
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+fn main() {
+    println!("{}", find_max_total(get_triangle()));
+}
+
+fn get_triangle() -> Vec<Vec<usize>> {
+    let file = File::open("triangle.txt").expect("Could not read file");
+    let reader = BufReader::new(file);
+    let mut grid = Vec::new();
+    for line in reader.lines() {
+        let line = line.expect("Could not get line");
+        let nums = line.split_whitespace().map(|num| num.parse::<usize>().expect("Could not parse")).collect();
+        grid.push(nums);
+    }
+    grid
+}
+
+fn find_max_total(grid: Vec<Vec<usize>>) -> usize {
+    let triangle_height = grid.len();
+    let mut idx = triangle_height - 1;
+    let mut highest_sums = match grid.get(idx) {
+        Some(sums) => sums.to_vec(),
+        None => panic!("Impossible path: check grid")
+    };
+    while idx > 0 {
+        idx -= 1;
+        let line = grid.get(idx).unwrap();
+        let mut new_highest_sums = Vec::new();
+        for (pos, &num) in line.iter().enumerate() {
+            new_highest_sums.push(max(num + highest_sums[pos], num + highest_sums[pos+1]))
+        }
+        highest_sums = new_highest_sums;
+    }
+    highest_sums[0]
+}
+
+#[cfg(test)]
+mod test_18 {
+    use crate::find_max_total;
+
+    #[test]
+    fn test_find_max_total() {
+        let grid = vec![
+            vec![3],
+            vec![7, 4],
+            vec![2, 4, 6],
+            vec![8, 5, 9, 3],
+        ];
+        assert_eq!(23, find_max_total(grid));
+    }
+
+}