dannygaobo的专栏

原创 iptables全景图

原创 promotion for 35 years coder-Day23-kmp算法

#include <iostream> #include <string.h> using namespace std; void getNext(char *pattern, int len, int* next) { int i = 0; int j = -1; next[0] = -1; while(i < len) { if (j == -1 || pattern[i] == pattern[j]) ...

原创 promotion for 35 years coder-Day22-省份数量

#include <iostream> #include <queue> using namespace std; int connection1[4][4] = {{1,0,1,1},{0,1,0,0},{1,0,1,1},{1,0,1,1}}; int connection2[4][4] = {{1,0,0,0},{0,1,0,0},{0,0,1,0},{0,0,0,1}}; //深度优先 void dfs(int array[4][4], int *flag, int po

原创 promotion for 35 years coder-Day21-morris中序遍历

#include <iostream> #include <queue> using namespace std; typedef struct treeNode_t { int val; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(int v, struct treeNode_t *pl, struct treeNode_t *pr) { ...

原创 promotion for 35 years coder-Day20-二叉树层序遍历

#include <iostream> #include <vector> #include <queue> using namespace std; typedef struct treeNode_t { int value; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(int v, struct treeNode_t *pl, stru...

原创 promotion for 35 years coder-Day19-二叉树后续遍历

#include <iostream> #include <stack> using namespace std; typedef struct treeNode_t { int value; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(int v, struct treeNode_t *pl, struct treeNode_t *pr) {...

原创 promotion for 35 years coder-Day18-二叉树中序遍历

#include <iostream> #include <stack> using namespace std; typedef struct treeNode_t { int value; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(int v, struct treeNode_t *pl, struct treeNode_t *pr) {...

原创 promotion for 35 years coder-Day17-二叉树前序遍历

#include <iostream> #include <stack> using namespace std; typedef struct treeNode_t { int value; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(int v, struct treeNode_t *pl, struct treeNode_t *pr) {...

原创 promotion for 35 years coder-Day16-有序数组求最大升序子序列长度

#include <iostream> using namespace std; int orderLen(int *array, int len) { int start = 0; int max = 0; for (int i = 1; i < len; i++) { if (array[i] < array[i - 1]) { int tmplen = i - start; ...

原创 promotion for 35 years coder-Day15-广度优先求二叉树最小深度

#include <iostream> #include <queue> using namespace std; typedef struct treeNode_t { int deep; struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(struct treeNode_t *pl, struct treeNode_t *pr) { ...

原创 promotion for 35 years coder-Day14-深度优先求二叉树最小深度

#include <iostream> using namespace std; typedef struct treeNode_t { struct treeNode_t *plchild; struct treeNode_t *prchild; treeNode_t(struct treeNode_t *pl, struct treeNode_t *pr) { plchild = pl; prchild = pr; ...

原创 promotion for 35 years coder-Day13-滑动窗口求子数组最大均值

#include <iostream> using namespace std; double maxSubArraySum(int *array, int len, int sublen) { if (len < sublen) { return -1.0; } int sum = 0; for (int i = 0; i < sublen; i++) { sum += array[i]; ...

原创 promotion for 35 years coder-Day12-合并有序数组

#include <iostream> #include <string.h> using namespace std; //base:array1d的实际空间长度等于两个数组长度之和 //空间复杂度O(n)，即归并排序 void merge1(int *array1, int len1, int *array2, int len2) { int *arrayTmp = new int[len1]; memcpy(arrayTmp, array1, len1 * ...

原创 promotion for 35 years coder-Day11-链表判定是否有环

#include <iostream> #include <set> using namespace std; struct T_LstNode; typedef struct T_LstNode { int value; T_LstNode *pNext; T_LstNode(int v, T_LstNode *next) { value = v; pNext = next; } }Node; //快...

原创 promotion for 35 years coder-Day10-两种方法求斐波拉契数列

#include <iostream> #include <string.h> using namespace std; //迭代法，时间复杂度O(n)，空间复杂度O(1) int iterator_Fibonacci(int n) { if (n < 2) return n; int lo = 0; int hi = 1; int sum = 0; for (int i = 2; i < n ...

原创 promotion for 35 years coder-Day09-双指针求有序数组两数之和

#include <iostream> using namespace std; int result[2] = {0}; void twoSum(int *pArray, int len, int target) { result[0] = -1; result[1] = -1; int lo = 0; int hi = len - 1; while(lo < hi) { int sum = pArray[lo]...

原创 promotion for 35 years coder-Day08-利用hash求无序数组两数之和

#include <iostream> #include <map> using namespace std; int result[2] = {0}; void gettarget(int *pArray, int len, int target) { result[0] = result[1] = -1; map<int, int> tag; for (int i = 0; i < len; i++) { ...

原创 promotion for 35 years coder-Day07-求无序数组三元素乘积最大值

思路： 当把元素排序后，分为三种情况 （1）元素全正：最大三个元素相乘即可 （2）元素全负：最大三个元素相乘即可 （3）有正有负：必须保证最后乘积为正才可能最大，最大值只可能有两种情况 最大三个数相乘，负数最小两个数相乘再和最大的数相乘 综上，结果就是max(min1*min2*max1, max1*max2*max3) 所以无需排序，只需遍历一遍找到上述5个值即可 #include <iostream> using namespace std; int getMax(int

原创 promotion for 35 years coder-Day06-牛顿法求平方根的整数部分

#include <iostream> #include <math.h> using namespace std; int newton(double factor, int dest) { if (factor < 0 || dest < 0) { return -1; } if (dest == 0 || dest == 1) { return dest; } doubl...

原创 promotion for 35 years coder-Day05-二分法求平方根整数部分

#include <iostream> #include <math.h> using namespace std; int findSqrt(int t) { if (t <= 0) { return -1; } if (t == 1) { return 1; } int index = -1; int lo = 2; int hi = t - 1; w...

原创 promotion for 35 years coder-Day04-求数组中两边和相等的位置

#include <iostream> using namespace std; int find_balance(int* array, int len) { int sum = 0; for (int i = 0; i < len; i++) { sum += array[i]; } int partSum = 0; for (int i = 0; i < len; i++) { if ...

原创 promotion for 35 years coder-Day03-去除排序数组重复数据，返回去重后数组长度，空间复杂度O(1)

include <iostream> using namespace std; int subject1[] = {1,2,2,2,3,3,4,4,4,4,5,7,9}; //result is 7 int subject2[] = {1,1,3,4,5,5,5,5,7,10,10,12,20,20}; //result is 8 int ArrayTrip(int *subject, int len) { if (NULL == subject) { ret...

原创 promotion for 35 years coder-Day02-素数

#include <iostream> #include <string.h> using namespace std; bool isPrime(int n) { for (int i = 2; i * i <= n; i++) { if (n % i == 0) { return false; } } return true; } int countPrim...

原创 promotion for 35 years coder-Day01-链表反转

#include <iostream> #include <string> struct T_LstNode; typedef struct T_LstNode { int value; T_LstNode *pNext; T_LstNode(int v, T_LstNode *next) { value = v; pNext = next; } }LstNode; //递归方式 LstNode *li...