diff --git a/2201/220111.cpp b/2201/220111.cpp new file mode 100644 index 0000000..8774300 --- /dev/null +++ b/2201/220111.cpp @@ -0,0 +1,40 @@ +#include + +// Definition for a binary tree node. +struct TreeNode { + int val; + TreeNode *left; + TreeNode *right; + TreeNode() : val(0), left(nullptr), right(nullptr) {} + explicit TreeNode(int x) : val(x), left(nullptr), right(nullptr) {} + TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {} + ~TreeNode() { delete this->left; delete this->right; } +}; + +/** + * 1022. Sum of Root To Leaf Binary Numbers + * You are given the root of a binary tree where each node has a value 0 or 1. Each root-to-leaf path represents a binary number starting with the most significant bit. + * For example, if the path is 0 -> 1 -> 1 -> 0 -> 1, then this could represent 01101 in binary, which is 13. + * For all leaves in the tree, consider the numbers represented by the path from the root to that leaf. Return the sum of these numbers. + * The test cases are generated so that the answer fits in a 32-bits integer. + */ + +class Solution { +public: + static int sumRootToLeaf(const TreeNode* root, int n = 0) { + if (!root->left && !root->right) + return n + root->val; + int ret = 0; + if (root->left) + ret += sumRootToLeaf(root->left, (n + root->val) << 1); + if (root->right) + ret += sumRootToLeaf(root->right, (n + root->val) << 1); + return ret; + } +}; + +int main() { + TreeNode head(1, new TreeNode(0, new TreeNode(0), new TreeNode(1)), new TreeNode(1, new TreeNode(0), new TreeNode(1))); + std::cout << Solution::sumRootToLeaf(&head); + return 0; +} diff --git a/2201/CMakeLists.txt b/2201/CMakeLists.txt index 4d867d2..2f58bdf 100644 --- a/2201/CMakeLists.txt +++ b/2201/CMakeLists.txt @@ -3,4 +3,4 @@ PROJECT(2201) SET(CMAKE_CXX_STANDARD 23) -ADD_EXECUTABLE(2201 220111-CN.cpp) \ No newline at end of file +ADD_EXECUTABLE(2201 220111.cpp) \ No newline at end of file