feat: resolved

Author: jtr109

n_ary_tree_level_order_traversal/src/lib.rs

@@ -0,0 +1,48 @@
+pub fn level_order(root: Vec<Option<i32>>) -> Vec<Vec<i32>> {
+    let mut res = vec![];
+    let mut current_level_cache = vec![];
+    let mut previous_level_node_count = 1;
+    let mut current_level_none_count = 0;
+    for n in root {
+        match n {
+            Some(v) => {
+                current_level_cache.push(v);
+                continue;
+            }
+            None => {
+                current_level_none_count += 1;
+                if current_level_none_count < previous_level_node_count {
+                    continue;
+                }
+                // the end of current level
+                res.push(current_level_cache.clone());
+                previous_level_node_count = current_level_cache.len();
+                current_level_cache = vec![];
+                current_level_none_count = 0;
+            }
+        }
+    }
+    res.push(current_level_cache);
+    return res;
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_example1() {
+        let root = vec![
+            Some(1),
+            None,
+            Some(3),
+            Some(2),
+            Some(4),
+            None,
+            Some(5),
+            Some(6),
+        ];
+        let expected = vec![vec![1], vec![3, 2, 4], vec![5, 6]];
+        assert_eq!(level_order(root), expected);
+    }
+}