Merge branch 'youngyangyang04:master' into master

This commit is contained in:
SianXiaoCHN
2022-03-19 10:57:17 -05:00
committed by GitHub
5 changed files with 30 additions and 20 deletions

View File

@ -174,6 +174,7 @@ const maxSubArray = nums => {
// 数组长度dp初始化
const len = nums.length;
let dp = new Array(len).fill(0);
dp[0] = nums[0];
// 最大值初始化为dp[0]
let max = dp[0];
for (let i = 1; i < len; i++) {

View File

@ -89,27 +89,26 @@ class Solution {
private:
bool backtracking (const string& s,
const unordered_set<string>& wordSet,
vector<int>& memory,
vector<bool>& memory,
int startIndex) {
if (startIndex >= s.size()) {
return true;
}
// 如果memory[startIndex]不是初始值了直接使用memory[startIndex]的结果
if (memory[startIndex] != -1) return memory[startIndex];
if (!memory[startIndex]) return memory[startIndex];
for (int i = startIndex; i < s.size(); i++) {
string word = s.substr(startIndex, i - startIndex + 1);
if (wordSet.find(word) != wordSet.end() && backtracking(s, wordSet, memory, i + 1)) {
memory[startIndex] = 1; // 记录以startIndex开始的子串是可以被拆分的
return true;
}
}
memory[startIndex] = 0; // 记录以startIndex开始的子串是不可以被拆分的
memory[startIndex] = false; // 记录以startIndex开始的子串是不可以被拆分的
return false;
}
public:
bool wordBreak(string s, vector<string>& wordDict) {
unordered_set<string> wordSet(wordDict.begin(), wordDict.end());
vector<int> memory(s.size(), -1); // -1 表示初始化状态
vector<bool> memory(s.size(), 1); // -1 表示初始化状态
return backtracking(s, wordSet, memory, 0);
}
};

View File

@ -325,6 +325,20 @@ var lowestCommonAncestor = function(root, p, q) {
};
```
## TypeScript
```typescript
function lowestCommonAncestor(root: TreeNode | null, p: TreeNode | null, q: TreeNode | null): TreeNode | null {
if (root === null || root === p || root === q) return root;
const left = lowestCommonAncestor(root.left, p, q);
const right = lowestCommonAncestor(root.right, p, q);
if (left !== null && right !== null) return root;
if (left !== null) return left;
if (right !== null) return right;
return null;
};
```
-----------------------

View File

@ -37,7 +37,7 @@
1. dp[i]的定义
**dp[i]表示i之前包括i的最长上升子序列的长度**
**dp[i]表示i之前包括i的以nums[i]结尾最长上升子序列的长度**
2. 状态转移方程

View File

@ -148,23 +148,19 @@ java版本1中创建了String数组多次使用Integer.parseInt了方法
版本2
class Solution {
public int monotoneIncreasingDigits(int n) {
if (n==0)return 0;
char[] chars= Integer.toString(n).toCharArray();
int start=Integer.MAX_VALUE;//start初始值设为最大值这是为了防止当数字本身是单调递增时没有一位数字需要改成9的情况
for (int i=chars.length-1;i>0;i--){
if (chars[i]<chars[i-1]){
chars[i-1]--;
start=i;
String s = String.valueOf(n);
char[] chars = s.toCharArray();
int start = s.length();
for (int i = s.length() - 2; i >= 0; i--) {
if (chars[i] > chars[i + 1]) {
chars[i]--;
start = i+1;
}
}
StringBuilder res=new StringBuilder();
for (int i=0;i<chars.length;i++){
if (chars[i]=='0'&&i==0)continue;//防止出现09这样的情况
if (i>=start){
res.append('9');
}else res.append(chars[i]);
for (int i = start; i < s.length(); i++) {
chars[i] = '9';
}
return Integer.parseInt(res.toString());
return Integer.parseInt(String.valueOf(chars));
}
}
```