day 11

Author: sachuverma

Leetcode Daily Challenge/April-2021/11. Deepest Leaves Sum.cpp

@@ -0,0 +1,65 @@
+/*
+Deepest Leaves Sum
+==================
+
+Given the root of a binary tree, return the sum of values of its deepest leaves.
+
+Example 1:
+Input: root = [1,2,3,4,5,null,6,7,null,null,null,null,8]
+Output: 15
+
+Example 2:
+Input: root = [6,7,8,2,7,1,3,9,null,1,4,null,null,null,5]
+Output: 19
+
+Constraints:
+The number of nodes in the tree is in the range [1, 104].
+1 <= Node.val <= 100
+
+Hint #1  
+Traverse the tree to find the max depth.
+
+Hint #2  
+Traverse the tree again to compute the sum required.
+*/
+
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+ * };
+ */
+
+class Solution
+{
+public:
+  int deepestLeavesSum(TreeNode *root)
+  {
+    int ans = 0;
+    queue<TreeNode *> pending;
+    pending.push(root);
+
+    while (pending.size())
+    {
+      int size = pending.size();
+      int curr_ans = 0;
+      for (int i = 0; i < size; ++i)
+      {
+        auto curr = pending.front();
+        pending.pop();
+        curr_ans += curr->val;
+        if (curr->left)
+          pending.push(curr->left);
+        if (curr->right)
+          pending.push(curr->right);
+      }
+      ans = curr_ans;
+    }
+    return ans;
+  }
+};

Leetcode Daily Challenge/April-2021/README.md

@@ -12,3 +12,4 @@
 | 8.  | [Letter Combinations of a Phone Number](https://leetcode.com/explore/challenge/card/april-leetcoding-challenge-2021/594/week-2-april-8th-april-14th/3701/)   |  [cpp](./08.%20Letter%20Combinations%20of%20a%20Phone%20Number.cpp)  |
 | 9.  | [Verifying an Alien Dictionary](https://leetcode.com/explore/challenge/card/april-leetcoding-challenge-2021/594/week-2-april-8th-april-14th/3702/)   |  [cpp](./09.%20Verifying%20an%20Alien%20Dictionary.cpp)  |
 | 10.  | [Longest Increasing Path in a Matrix](https://leetcode.com/explore/challenge/card/april-leetcoding-challenge-2021/594/week-2-april-8th-april-14th/3703/)   |  [cpp](./10.%20Longest%20Increasing%20Path%20in%20a%20Matrix.cpp)  |
+| 11.  | [Deepest Leaves Sum](https://leetcode.com/explore/challenge/card/april-leetcoding-challenge-2021/594/week-2-april-8th-april-14th/3704/)   |  [cpp](./11.%20Deepest%20Leaves%20Sum.cpp)  |