姚军

分析题目：CM74 下一个较大元素思路：保留最大元素，右下降栈代码class NextElement {public: vector<int> findNext(vector<int> A, int n) { // write code here vector<int> res(n); stack<int> stk; for(int i = n-1; i >= 0; i

题目类型：树难度：2题意：使用有序数组构建二叉查找树，标准模板题。注意树的定义在类之前有写，不需要自己重写。class MinimalBST {public: int buildMinimalBST(vector<int> vals) { TreeNode* root = build(vals, 0, vals.size()-1); ...

题目类型：单调双栈 二分题意：找到大于当前数的最小值。版本1set有序二分查找34msclass NextElement {public: vector<int> findNext(vector<int> A, int n) { vector<int> res(n, -1); set<int> st...

把做括号视为1，有括号视为-1，在字符串的遍历过程中保证前缀和为非负同时反向做一遍，但是此时右括号为1，左括号为-1，保证前缀和为非负class Parenthesis {public: bool chkParenthesis(string A, int n) { int x = 0; for(auto c: A){ if(c=...

数组要初始化为0class Robot {public: int dp[13]={0}; int countWays(int x, int y) { for(int i = 1; i <= x; i++) for(int j = 1; j <= y; j++){ if(i==1 &&am...

(a+b)%c = ((a%c)+(b%c))%c两次取模class GoUpstairs {public: const int N = 1e5+5; const int M = 1e9+7; int countWays(int n) { int F[N]; F[1] = 1; F[2] = 2; F[3...

阶乘后面0的数量跟5有关直接除class Factor {public: int getFactorSuffixZero(int n) { int res = 0; while(n){ res += n/5; n /= 5; } return res; }};...

/*struct TreeNode { int val; struct TreeNode *left; struct TreeNode *right; TreeNode(int x) : val(x), left(NULL), right(NULL) { }};*/class Balance {public: boo...

rand()函数产生伪随机数，可以生成0到rand_max之间的一个随机数 srand()提供种子，称为随机数生成器的初始化器 头文件stdlib.h 下面是根据种子生成的1-6之间的10个随机数#include#includeint main(){ unsigned int seed; while(scanf("%d",&seed) != EOF){ sra

class LCA {public: int getLCA(int a, int b) { map<int, bool> mp; while(a){ mp[a] = true; a = a/2; } while(b){ if(mp[b]== t...

大神代码class Exchange {public: int exchangeOddEven(int x) { int oddVal = (x & 0xAAAAAAAA); // bit 1 3 5 ... 31 int evenVal = (x & 0x55555555); // bit 0 2 4 ... 30 re...

class Transform {public: int calcCost(int x, int y) { string a = bitset<32>(x).to_string(); string b = bitset<32>(y).to_string(); int cnt = 0; for(int i =...

class Count2 {public: int countNumberOf2s(int n) { string str = to_string(n); int res = 0; for(int i = 0; i < str.size(); i++){ int l = 0, r = 0, p = 1; ...

题目链接/*struct ListNode { int val; struct ListNode *next; ListNode(int x) : val(x), next(NULL) {}};*/class Partition {public: ListNode* partition(ListNode* p, int x) { //用两个...

题目链接class Clearer {public: vector<vector<int> > clearZero(vector<vector<int> > mat, int n) { int x[505]={0}, y[505]={0}; for(int i = 0; i < n; i++){ ...