20250207 finished.

src/problem/mod.rs

@@ -474,3 +474,5 @@ mod p922_sort_array_by_parity_ii;
 mod p90_subsets_ii;
 
 mod p47_permutations_ii;
+
+mod p59_spiral_matrix_ii;

src/problem/p59_spiral_matrix_ii.rs

@@ -0,0 +1,54 @@
+/**
+ * [59] Spiral Matrix II
+ */
+pub struct Solution {}
+
+// submission codes start here
+
+const DIRECTIONS: [(i32, i32); 4] = [(0, 1), (1, 0), (0, -1), (-1, 0)];
+
+impl Solution {
+    pub fn generate_matrix(n: i32) -> Vec<Vec<i32>> {
+        let mut result = vec![vec![0; n as usize]; n as usize];
+        let (mut x, mut y) = (0, 0);
+        let mut pos = 0;
+
+        for i in 1..=n.pow(2) {
+            result[x as usize][y as usize] = i;
+
+            let (next_x, next_y) = (x + DIRECTIONS[pos].0, y + DIRECTIONS[pos].1);
+
+            if next_x < 0
+                || next_x >= n
+                || next_y < 0
+                || next_y >= n
+                || result[next_x as usize][next_y as usize] != 0
+            {
+                pos = (pos + 1) % 4;
+                x = x + DIRECTIONS[pos].0;
+                y = y + DIRECTIONS[pos].1;
+            } else {
+                x = next_x;
+                y = next_y;
+            }
+        }
+
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_59() {
+        assert_eq!(vec![vec![1]], Solution::generate_matrix(1));
+        assert_eq!(
+            vec![vec![1, 2, 3], vec![8, 9, 4], vec![7, 6, 5]],
+            Solution::generate_matrix(3)
+        );
+    }
+}