标签：
Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent
a number.
An example is the root-to-leaf path 1->2->3 which represents the number 123.
Find the total sum of all root-to-leaf numbers.
For example,
1 / 2 3
The root-to-leaf path 1->2 represents the number 12.
The root-to-leaf path 1->3 represents the number 13.
Return the sum = 12 + 13 = 25.
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class Solution {
public:
int sumNumbers(TreeNode* root) {
return dfs(root, 0);
}
int dfs(TreeNode* root, int sum){
if (root == 0) return 0;
if (root->left == NULL && root->right == NULL)
{
return sum * 10 + root->val;
}
return dfs(root->left, sum * 10 + root->val) + dfs(root->right, sum * 10 + root->val);
}
};
#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:
int sumNumbers(TreeNode* root) {
return dfs(root, 0);
}
int dfs(TreeNode* root, int sum){
if (root == 0) return 0;
if (root->left == NULL && root->right == NULL)
{
return sum * 10 + root->val;
}
return dfs(root->left, sum * 10 + root->val) + dfs(root->right, sum * 10 + root->val);
}
};
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;
createTree(root);
int path = s.sumNumbers(root);
cout << path <<endl;
system("pause");
return 0;
}
LeetCode 129:Sum Root to Leaf Numbers
标签：
原文地址：http://blog.csdn.net/geekmanong/article/details/50441447
