二叉树的层次遍历

src/test/java/com/ossez/lang/tutorial/tests/LintcodeTest.java

@@ -290,28 +290,4 @@ public class LintcodeTest {
 		System.out.println(strSet.size());
 	}
 
-	/**
-	 * 1480 https://www.lintcode.com/problem/dot-product/description
-	 */
-	@Test
-	public void test1480dotProduct() {
-		int[] A = { 1, 1, -1 };
-		int[] B = { 2147483647, 1, 3 };
-
-		int retStatus = 0;
-
-		// LENGTH CHECK
-		if (A.length == 0 || B.length == 0 || A.length != B.length)
-			retStatus = -1;
-
-		// ADDED
-		if (retStatus != -1) {
-			for (int i = 0; i < A.length; i++) {
-				retStatus = retStatus + A[i] * B[i];
-			}
-		}
-
-		System.out.println(retStatus);
-	}
-
 }

src/test/java/com/ossez/lang/tutorial/tests/lintcode/LintCode0069SLevelOrderTest.java

@@ -0,0 +1,124 @@
+package com.ossez.lang.tutorial.tests.lintcode;
+
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.ossez.lang.tutorial.models.TreeNode;
+
+/**
+ * <p>
+ * 69
+ * <ul>
+ * <li>@see <a href=
+ * "https://www.cwiki.us/display/ITCLASSIFICATION/Binary+Tree+Level+Order+Traversal">https://www.cwiki.us/display/ITCLASSIFICATION/Binary+Tree+Level+Order+Traversal</a>
+ * <li>@see<a href=
+ * "https://www.lintcode.com/problem/binary-tree-level-order-traversal">https://www.lintcode.com/problem/binary-tree-level-order-traversal</a>
+ * </ul>
+ * </p>
+ * 
+ * @author YuCheng
+ *
+ */
+public class LintCode0069SLevelOrderTest {
+
+	private final static Logger logger = LoggerFactory.getLogger(LintCode0069SLevelOrderTest.class);
+
+	/**
+	 * 
+	 */
+	@Test
+	public void testMain() {
+		logger.debug("BEGIN");
+		String data = "{3,9,20,#,#,15,7}";
+
+		TreeNode tn = deserialize(data);
+		System.out.println(levelOrder(tn));
+
+	}
+
+	/**
+	 * Deserialize from array to tree
+	 * 
+	 * @param data
+	 * @return
+	 */
+	private TreeNode deserialize(String data) {
+		// NULL CHECK
+		if (data.equals("{}")) {
+			return null;
+		}
+
+		ArrayList<TreeNode> treeList = new ArrayList<TreeNode>();
+
+		data = data.replace("{", "");
+		data = data.replace("}", "");
+		String[] vals = data.split(",");
+
+		// INSERT ROOT
+		TreeNode root = new TreeNode(Integer.parseInt(vals[0]));
+		treeList.add(root);
+
+		int index = 0;
+		boolean isLeftChild = true;
+		for (int i = 1; i < vals.length; i++) {
+			if (!vals[i].equals("#")) {
+				TreeNode node = new TreeNode(Integer.parseInt(vals[i]));
+				if (isLeftChild) {
+					treeList.get(index).left = node;
+				} else {
+					treeList.get(index).right = node;
+				}
+				treeList.add(node);
+			}
+
+			// LEVEL
+			if (!isLeftChild) {
+				index++;
+			}
+
+			// MOVE TO RIGHT OR NEXT LEVEL
+			isLeftChild = !isLeftChild;
+		}
+
+		return root;
+
+	}
+
+	private List<List<Integer>> levelOrder(TreeNode root) {
+		Queue<TreeNode> queue = new LinkedList<TreeNode>();
+		List<List<Integer>> rs = new ArrayList<List<Integer>>();
+
+		// NULL CHECK
+		if (root == null) {
+			return rs;
+		}
+
+		queue.offer(root);
+
+		while (!queue.isEmpty()) {
+			int length = queue.size();
+			List<Integer> list = new ArrayList<Integer>();
+
+			for (int i = 0; i < length; i++) {
+				TreeNode curTN = queue.poll();
+				list.add(curTN.val);
+				if (curTN.left != null) {
+					queue.offer(curTN.left);
+				}
+				if (curTN.right != null) {
+					queue.offer(curTN.right);
+				}
+			}
+
+			rs.add(list);
+		}
+
+		return rs;
+	}
+}