leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
Log | Files | Refs | README | LICENSE |
commit558b26de15c97da88cb6cce6f430348e1100ad84
parentf3d6d1c6a9fd52d28c12847703641ae18970d711
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateThu, 16 Mar 2023 22:21:04 +0100

Daily Problem

Diffstat:
AProblems/0106.cpp|++++++++++++++++++++++++++++++++
MREADME.md|+

2 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/Problems/0106.cpp b/Problems/0106.cpp

@@ -0,0 +1,32 @@

class Solution {
class Record {
public:
int low, high;
TreeNode **field;
Record(int l, int h, TreeNode **f) : low(l), high(h), field(f) {}
};
public:
TreeNode *buildTree(vector<int> &inorder, vector<int> &postorder) {
unordered_map<int, int> um;
for (int i = 0; i < inorder.size(); i++) um[inorder[i]] = i;
int crnt = postorder.size() - 1;
TreeNode head, *nw;
stack<Record> st;
st.push({0, (int)inorder.size(), &head.right});
while (!st.empty()) {
Record r = st.top();
st.pop();
while (r.low < r.high) {
int pos = um[postorder[crnt]];
nw = *r.field = new TreeNode(postorder[crnt--]);
st.push({r.low, pos, &nw->left});
r.low = pos + 1;
r.field = &nw->right;
}
}
return head.right;
}
};

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

@@ -103,6 +103,7 @@ for solving problems.

| 0103 | Medium | [Binary Tree Zigzag Level Order Traversal](Problems/0103.cpp) |
| 0104 | Easy | [Maximum Depth of Binary Tree](Problems/0104.cpp) |
| 0105 | Medium | [Construct Binary Tree from Preorder and Inorder Traversal](Problems/0105.cpp) |
| 0106 | Medium | [Construct Binary Tree from Inorder and Postorder Traversal](Problems/0106.cpp) |
| 0107 | Medium | [Binary Tree Level Order Traversal II](Problems/0107.cpp) |
| 0108 | Easy | [Convert Sorted Array to Binary Search Tree](Problems/0108.cpp) |
| 0109 | Medium | [Convert Sorted List to Binary Search Tree](Problems/0109.cpp) |