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feat: add solutions to lc problem: No.1305
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No.1305.All Elements in Two Binary Search Trees
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@yanglbme
yanglbme committed Dec 4, 2024
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302 changes: 155 additions & 147 deletions solution/1300-1399/1305.All Elements in Two Binary Search Trees/README.md
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Expand Up @@ -59,7 +59,11 @@ tags:

<!-- solution:start -->

### 方法一
### 方法一：DFS + 归并

由于两棵树都是二叉搜索树，所以我们可以通过中序遍历得到两棵树的节点值序列 $\textit{a}$ 和 $\textit{b}$，然后使用双指针归并两个有序数组，得到最终的答案。

时间复杂度 $O(n+m)$，空间复杂度 $O(n+m)$。其中 $n$ 和 $m$ 分别是两棵树的节点数。

<!-- tabs:start -->

Expand All @@ -73,36 +77,36 @@ tags:
# self.left = left
# self.right = right
class Solution:
def getAllElements(self, root1: TreeNode, root2: TreeNode) -> List[int]:
def dfs(root, t):
def getAllElements(
self, root1: Optional[TreeNode], root2: Optional[TreeNode]
) -> List[int]:
def dfs(root: Optional[TreeNode], nums: List[int]) -> int:
if root is None:
return
dfs(root.left, t)
t.append(root.val)
dfs(root.right, t)

def merge(t1, t2):
ans = []
i = j = 0
while i < len(t1) and j < len(t2):
if t1[i] <= t2[j]:
ans.append(t1[i])
i += 1
else:
ans.append(t2[j])
j += 1
while i < len(t1):
ans.append(t1[i])
dfs(root.left, nums)
nums.append(root.val)
dfs(root.right, nums)

a, b = [], []
dfs(root1, a)
dfs(root2, b)
m, n = len(a), len(b)
i = j = 0
ans = []
while i < m and j < n:
if a[i] <= b[j]:
ans.append(a[i])
i += 1
while j < len(t2):
ans.append(t2[j])
else:
ans.append(b[j])
j += 1
return ans

t1, t2 = [], []
dfs(root1, t1)
dfs(root2, t2)
return merge(t1, t2)
while i < m:
ans.append(a[i])
i += 1
while j < n:
ans.append(b[j])
j += 1
return ans
```

#### Java
Expand All @@ -125,40 +129,37 @@ class Solution:
*/
class Solution {
public List<Integer> getAllElements(TreeNode root1, TreeNode root2) {
List<Integer> t1 = new ArrayList<>();
List<Integer> t2 = new ArrayList<>();
dfs(root1, t1);
dfs(root2, t2);
return merge(t1, t2);
}

private void dfs(TreeNode root, List<Integer> t) {
if (root == null) {
return;
}
dfs(root.left, t);
t.add(root.val);
dfs(root.right, t);
}

private List<Integer> merge(List<Integer> t1, List<Integer> t2) {
List<Integer> ans = new ArrayList<>();
List<Integer> a = new ArrayList<>();
List<Integer> b = new ArrayList<>();
dfs(root1, a);
dfs(root2, b);
int m = a.size(), n = b.size();
int i = 0, j = 0;
while (i < t1.size() && j < t2.size()) {
if (t1.get(i) <= t2.get(j)) {
ans.add(t1.get(i++));
List<Integer> ans = new ArrayList<>();
while (i < m && j < n) {
if (a.get(i) <= b.get(j)) {
ans.add(a.get(i++));
} else {
ans.add(t2.get(j++));
ans.add(b.get(j++));
}
}
while (i < t1.size()) {
ans.add(t1.get(i++));
while (i < m) {
ans.add(a.get(i++));
}
while (j < t2.size()) {
ans.add(t2.get(j++));
while (j < n) {
ans.add(b.get(j++));
}
return ans;
}

private void dfs(TreeNode root, List<Integer> nums) {
if (root == null) {
return;
}
dfs(root.left, nums);
nums.add(root.val);
dfs(root.right, nums);
}
}
```

Expand All @@ -179,33 +180,36 @@ class Solution {
class Solution {
public:
vector<int> getAllElements(TreeNode* root1, TreeNode* root2) {
vector<int> t1;
vector<int> t2;
dfs(root1, t1);
dfs(root2, t2);
return merge(t1, t2);
}
vector<int> a, b, ans;
dfs(root1, a);
dfs(root2, b);

void dfs(TreeNode* root, vector<int>& t) {
if (!root) return;
dfs(root->left, t);
t.push_back(root->val);
dfs(root->right, t);
}

vector<int> merge(vector<int>& t1, vector<int>& t2) {
vector<int> ans;
int i = 0, j = 0;
while (i < t1.size() && j < t2.size()) {
if (t1[i] <= t2[j])
ans.push_back(t1[i++]);
else
ans.push_back(t2[j++]);
while (i < a.size() && j < b.size()) {
if (a[i] <= b[j]) {
ans.push_back(a[i++]);
} else {
ans.push_back(b[j++]);
}
}
while (i < a.size()) {
ans.push_back(a[i++]);
}
while (j < b.size()) {
ans.push_back(b[j++]);
}
while (i < t1.size()) ans.push_back(t1[i++]);
while (j < t2.size()) ans.push_back(t2[j++]);
return ans;
}

private:
void dfs(TreeNode* root, vector<int>& nums) {
if (root == nullptr) {
return;
}
dfs(root->left, nums);
nums.push_back(root->val);
dfs(root->right, nums);
}
};
```

Expand All @@ -220,42 +224,37 @@ public:
* Right *TreeNode
* }
*/
func getAllElements(root1 *TreeNode, root2 *TreeNode) []int {
var dfs func(root *TreeNode) []int
dfs = func(root *TreeNode) []int {
func getAllElements(root1 *TreeNode, root2 *TreeNode) (ans []int) {
var dfs func(*TreeNode, *[]int)
dfs = func(root *TreeNode, nums *[]int) {
if root == nil {
return []int{}
return
}
left := dfs(root.Left)
right := dfs(root.Right)
left = append(left, root.Val)
left = append(left, right...)
return left
dfs(root.Left, nums)
*nums = append(*nums, root.Val)
dfs(root.Right, nums)
}
merge := func(t1, t2 []int) []int {
var ans []int
i, j := 0, 0
for i < len(t1) && j < len(t2) {
if t1[i] <= t2[j] {
ans = append(ans, t1[i])
i++
} else {
ans = append(ans, t2[j])
j++
}
}
for i < len(t1) {
ans = append(ans, t1[i])
a, b := []int{}, []int{}
dfs(root1, &a)
dfs(root2, &b)
i, j := 0, 0
m, n := len(a), len(b)
for i < m && j < n {
if a[i] < b[j] {
ans = append(ans, a[i])
i++
}
for j < len(t2) {
ans = append(ans, t2[j])
} else {
ans = append(ans, b[j])
j++
}
return ans
}
t1, t2 := dfs(root1), dfs(root2)
return merge(t1, t2)
for ; i < m; i++ {
ans = append(ans, a[i])
}
for ; j < n; j++ {
ans = append(ans, b[j])
}
return
}
```

Expand All @@ -277,31 +276,35 @@ func getAllElements(root1 *TreeNode, root2 *TreeNode) []int {
*/

function getAllElements(root1: TreeNode | null, root2: TreeNode | null): number[] {
const res = [];
const stacks = [[], []];
while (root1 != null || stacks[0].length !== 0 || root2 != null || stacks[1].length !== 0) {
if (root1 != null) {
stacks[0].push(root1);
root1 = root1.left;
} else if (root2 != null) {
stacks[1].push(root2);
root2 = root2.left;
const dfs = (root: TreeNode | null, nums: number[]) => {
if (!root) {
return;
}
dfs(root.left, nums);
nums.push(root.val);
dfs(root.right, nums);
};
const a: number[] = [];
const b: number[] = [];
dfs(root1, a);
dfs(root2, b);
const [m, n] = [a.length, b.length];
const ans: number[] = [];
let [i, j] = [0, 0];
while (i < m && j < n) {
if (a[i] < b[j]) {
ans.push(a[i++]);
} else {
if (
(stacks[0][stacks[0].length - 1] ?? { val: Infinity }).val <
(stacks[1][stacks[1].length - 1] ?? { val: Infinity }).val
) {
const { val, right } = stacks[0].pop();
res.push(val);
root1 = right;
} else {
const { val, right } = stacks[1].pop();
res.push(val);
root2 = right;
}
ans.push(b[j++]);
}
}
return res;
while (i < m) {
ans.push(a[i++]);
}
while (j < n) {
ans.push(b[j++]);
}
return ans;
}
```

Expand Down Expand Up @@ -333,41 +336,46 @@ impl Solution {
root1: Option<Rc<RefCell<TreeNode>>>,
root2: Option<Rc<RefCell<TreeNode>>>,
) -> Vec<i32> {
fn dfs(root: &Option<Rc<RefCell<TreeNode>>>, t: &mut Vec<i32>) {
if let Some(root) = root {
dfs(&root.borrow().left, t);
t.push(root.borrow().val);
dfs(&root.borrow().right, t);
}
}
let mut a = Vec::new();
let mut b = Vec::new();

let mut t1 = Vec::new();
let mut t2 = Vec::new();
dfs(&root1, &mut t1);
dfs(&root2, &mut t2);
Solution::dfs(&root1, &mut a);
Solution::dfs(&root2, &mut b);

let mut ans = Vec::new();
let mut i = 0;
let mut j = 0;
while i < t1.len() && j < t2.len() {
if t1[i] < t2[j] {
ans.push(t1[i]);
let (mut i, mut j) = (0, 0);

while i < a.len() && j < b.len() {
if a[i] <= b[j] {
ans.push(a[i]);
i += 1;
} else {
ans.push(t2[j]);
ans.push(b[j]);
j += 1;
}
}
while i < t1.len() {
ans.push(t1[i]);

while i < a.len() {
ans.push(a[i]);
i += 1;
}
while j < t2.len() {
ans.push(t2[j]);

while j < b.len() {
ans.push(b[j]);
j += 1;
}

ans
}

fn dfs(root: &Option<Rc<RefCell<TreeNode>>>, nums: &mut Vec<i32>) {
if let Some(node) = root {
let node = node.borrow();
Solution::dfs(&node.left, nums);
nums.push(node.val);
Solution::dfs(&node.right, nums);
}
}
}
```

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