Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum.
For example:Given the below binary tree and
sum
= 22
,
5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1
return
[ [5,4,11,2], [5,8,4,5] ]
Subscribe to see which companies asked this question
class Solution { public: vector<vector<int>> pathSum(TreeNode* root, int sum) { vector<vector<int>> res; vector<int> tmp; //保存中间结果 tmpFunction(root, sum, tmp, res); return res; } void tmpFunction(TreeNode* root, int sum, vector<int> &tmp, vector<vector<int>>&res){ if (root == NULL) return; tmp.push_back(root->val); if (root->left == NULL && root->right == NULL){ if (root->val == sum) res.push_back(tmp); } tmpFunction(root->left, sum - root->val, tmp, res); tmpFunction(root->right, sum - root->val, tmp, res); tmp.pop_back(); } };
#include<iostream> #include<new> #include<vector> using namespace std; //Definition for binary tree struct TreeNode { int val; TreeNode *left; TreeNode *right; TreeNode(int x) : val(x), left(NULL), right(NULL) {} }; class Solution { public: vector<vector<int> > pathSum(TreeNode *root, int sum) { vector<vector<int> > path; vector<int> tmp; hasPathSum(root, sum, path, tmp); return path; } void hasPathSum(TreeNode *root, int sum, vector<vector<int> > &path, vector<int> tmp) { if (root == NULL) return; tmp.push_back(root->val); if (root->left == NULL&&root->right == NULL && (sum - root->val) == 0) { path.push_back(tmp); } if (root->left) hasPathSum(root->left, sum - root->val, path, tmp); if (root->right) hasPathSum(root->right, sum - root->val, path, tmp); tmp.pop_back(); } void createTree(TreeNode *&root) { int i; cin >> i; if (i != 0) { root = new TreeNode(i); if (root == NULL) return; createTree(root->left); createTree(root->right); } } }; int main() { Solution s; TreeNode *root; s.createTree(root); vector<vector<int> > path = s.pathSum(root, 22); for (auto a : path) { for (auto v : a) cout << v << " "; cout << endl; } system("pause"); return 0; }
【推荐】编程新体验,更懂你的AI,立即体验豆包MarsCode编程助手
【推荐】凌霞软件回馈社区,博客园 & 1Panel & Halo 联合会员上线
【推荐】抖音旗下AI助手豆包,你的智能百科全书,全免费不限次数
【推荐】博客园社区专享云产品让利特惠,阿里云新客6.5折上折
【推荐】轻量又高性能的 SSH 工具 IShell:AI 加持,快人一步