leetcode

Data Structure II: Day 16

2 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/ Problems/0113.cpp b/ Problems/0113.cpp

@@ -0,0 +1,26 @@

class Solution {

public:

vector<vector<int>> pathSum(TreeNode *root, int targetSum) {

if (!root) return {};

stack<pair<TreeNode *, int>> st;

vector<vector<int>> res;

vector<int> path;

st.push({root, 0});

while (!st.empty()) {

auto [root, sum] = st.top();

if (sum == INT_MIN) {

st.pop();

path.pop_back();

continue;

}

sum += root->val;

st.top().second = INT_MIN;

path.push_back(root->val);

if (!root->left && !root->right && sum == targetSum) res.push_back(path);

if (root->left) st.push({root->left, sum});

if (root->right) st.push({root->right, sum});

}

return res;

}

};

diff --git a/ README.md b/ README.md

@@ -104,6 +104,7 @@ for solving problems. | 0110 | Easy | [Balanced Binary Tree](Problems/0110.cpp) | | 0111 | Easy | [Minimum Depth of Binary Tree](Problems/0111.cpp) | | 0112 | Easy | [Path Sum](Problems/0112.cpp) |

| 0113 | Medium | [Path Sum II](Problems/0113.cpp) |

| 0114 | Medium | [Flatten Binary Tree to Linked List](Problems/0114.cpp) | | 0116 | Medium | [Populating Next Right Pointers in Each Node](Problems/0116.cpp) | | 0117 | Medium | [Populating Next Right Pointers in Each Node II](Problems/0117.cpp) |