leetcode

Data Structure II: Day 18

2 files changed, 42 insertions(+), 0 deletions(-)

diff --git a/ Problems/0297.cpp b/ Problems/0297.cpp

@@ -0,0 +1,41 @@

class Codec {

public:

string serialize(TreeNode *root) {

ostringstream out;

serialize(root, out);

return out.str();

}

TreeNode *deserialize(string data) {

istringstream in(data);

return deserialize(in);

}

private:

void serialize(TreeNode *root, ostringstream &out) {

stack<TreeNode *> st;

st.push(root);

while (!st.empty()) {

TreeNode *root = st.top();

st.pop();

if (!root)

out << "# ";

else {

out << root->val << ' ';

st.push(root->right);

st.push(root->left);

}

}

}

TreeNode *deserialize(istringstream &in) {

string val;

in >> val;

if (val == "#") return nullptr;

TreeNode *root = new TreeNode(stoi(val));

root->left = deserialize(in);

root->right = deserialize(in);

return root;

}

};

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

@@ -190,6 +190,7 @@ for solving problems. | 0287 | Medium | [Find the Duplicate Number](Problems/0287.cpp) | | 0290 | Easy | [Word Pattern](Problems/0290.cpp) | | 0295 | Hard | [Find Median from Data Stream](Problems/0295.cpp) |

| 0297 | Hard | [Serialize and Deserialize Binary Tree](Problems/0297.cpp) |

| 0299 | Medium | [Bulls and Cows](Problems/0299.cpp) | | 0300 | Medium | [Longest Increasing Subsequence](Problems/0300.cpp) | | 0304 | Medium | [Range Sum Query 2D - Immutable](Problems/0304.cpp) |