✨ [102] dfs without lvl variables

Author: enkr1

102/my_solution.js

@@ -16,46 +16,85 @@ const levelOrder = (root) => {
   let list = [[root.val]], children = 2, visitedChildren = 0, nullChildren = 0, level = 1, queue = [root], levelVal = [];
 
   while (queue.length > 0) {
-    let curr = queue.shift(), left = curr.left, right = curr.right;
     console.log(`-> level:${level}, children:${children}, visitedChildren:${visitedChildren}, nullChildren:${nullChildren}, levelVal:${levelVal}`)
-    console.log(curr)
-    if (null !== left) {
-      queue.push(left);
-      visitedChildren++;
-      levelVal.push(left.val);
-    } else {
-      nullChildren++;
-    }
 
-    if (null !== right) {
-      queue.push(right);
-      visitedChildren++;
-      levelVal.push(right.val);
-    } else {
-      nullChildren++;
-    }
+    let l = queue.length, singleLevel = [];
+
+    while (l > 0) {
+      console.log("queue");
+      console.log(list);
+      console.log(queue);
+      console.log(l);
+      console.log(queue.length);
 
-    console.log(`--> level:${level}, children:${children}, visitedChildren:${visitedChildren}, nullChildren:${nullChildren}, levelVal:${levelVal}`)
+      let curr = queue.shift(), left = curr.left, right = curr.right;
 
-    if (children === (visitedChildren + nullChildren)) {
+      if (null !== left) {
+        queue.push(left);
+        singleLevel.push(left.val);
+      }
 
-      // if (undefined === list[level]) {
-      if (levelVal.length > 0) list[level] = levelVal;
-      // } else {
-      //   list[level] = list[level].concat(levelVal)
-      // }
-      levelVal = [];
-      children *= 2;
-      level++;
-      visitedChildren = 0;
-      nullChildren *= 2;
+      if (null !== right) {
+        queue.push(right);
+        singleLevel.push(right.val);
+      }
+
+      l--;
     }
+
+    if (singleLevel.length > 0) list.push(singleLevel);
   }
 
   console.log(list);
 
   return list;
 };
+// const levelOrder = (root) => {
+//   if (null === root) return [];
+//
+//   let list = [[root.val]], children = 2, visitedChildren = 0, nullChildren = 0, level = 1, queue = [root], levelVal = [];
+//
+//   while (queue.length > 0) {
+//     let curr = queue.shift(), left = curr.left, right = curr.right;
+//     console.log(`-> level:${level}, children:${children}, visitedChildren:${visitedChildren}, nullChildren:${nullChildren}, levelVal:${levelVal}`)
+//     console.log(curr)
+//     if (null !== left) {
+//       queue.push(left);
+//       visitedChildren++;
+//       levelVal.push(left.val);
+//     } else {
+//       nullChildren++;
+//     }
+//
+//     if (null !== right) {
+//       queue.push(right);
+//       visitedChildren++;
+//       levelVal.push(right.val);
+//     } else {
+//       nullChildren++;
+//     }
+//
+//     console.log(`--> level:${level}, children:${children}, visitedChildren:${visitedChildren}, nullChildren:${nullChildren}, levelVal:${levelVal}`)
+//
+//     if (children === (visitedChildren + nullChildren)) {
+//
+//       // if (undefined === list[level]) {
+//       if (levelVal.length > 0) list[level] = levelVal;
+//       // } else {
+//       //   list[level] = list[level].concat(levelVal)
+//       // }
+//       levelVal = [];
+//       children *= 2;
+//       level++;
+//       visitedChildren = 0;
+//       nullChildren *= 2;
+//     }
+//   }
+//
+//   console.log(list);
+//
+//   return list;
+// };
 
 // [1,2,null,3,null,4,null,5]
 let x =

102/solution.js

@@ -1,47 +1,40 @@
-/**
- * Definition for a binary tree node.
- * function TreeNode(val, left, right) {
- *     this.val = (val===undefined ? 0 : val)
- *     this.left = (left===undefined ? null : left)
- *     this.right = (right===undefined ? null : right)
- * }
- */
+class TreeNode {
+  constructor(val, left, right) {
+    this.val = (val === undefined ? 0 : val);
+    this.left = (left === undefined ? null : left);
+    this.right = (right === undefined ? null : right);
+  }
+}
+
 /**
  * @param {TreeNode} root
  * @return {number[][]}
  */
 const levelOrder = (root) => {
   if (null === root) return [];
 
-  let list = [[root.val]], children = 2, visitedChildren = 0, nullChildren = 0, level = 1, queue = [root], levelVal = [];
+  let list = [[root.val]], queue = [root];
 
   while (queue.length > 0) {
-    let curr = queue.shift(), left = curr.left, right = curr.right;
-
-    if (null !== left) {
-      queue.push(left);
-      visitedChildren++;
-      levelVal.push(left.val);
-    } else {
-      nullChildren++;
-    }
+    let l = queue.length, singleLevel = [];
 
-    if (null !== right) {
-      queue.push(right);
-      visitedChildren++;
-      levelVal.push(right.val);
-    } else {
-      nullChildren++;
-    }
+    while (l > 0) {
+      let curr = queue.shift(), left = curr.left, right = curr.right;
+
+      if (null !== left) {
+        queue.push(left);
+        singleLevel.push(left.val);
+      }
 
-    if (children === (visitedChildren + nullChildren)) {
-      if (levelVal.length > 0) list[level] = levelVal;
-      levelVal = [];
-      level++;
-      children *= 2;
-      visitedChildren = 0;
-      nullChildren *= 2;
+      if (null !== right) {
+        queue.push(right);
+        singleLevel.push(right.val);
+      }
+
+      l--;
     }
+
+    if (singleLevel.length > 0) list.push(singleLevel);
   }
 
   return list;