算法-直接插入排序

一、总体思想：将一个记录直接插入到一个已经排序好的列表中的对应位置，形成一个新的列表。直接插入排序为稳定排序。

二、排序过程(升序)： 1、认为第一个记录为有序列表。 2、从第二个记录开始，依次和已经排序的列表中记录做比较，如果被比较记录大于该记录， 则将被比较记录后移一位，否则将该记录插入到不大于它的记录之后。 3、依次处理后续记录。

三、算法效率 时间复杂度：O(n^2) 空间复杂度：O(1)

四、代码-数组实现方式

/******************************************** Author: zchshen Date: 2017-07-09 Brief: ascending order of insert sort by array. ********************************************/ #include <iostream> #include <stdlib.h> #include <string.h> const int MaxArraySize = 128; void InsertSortUp(int *array, const int &count){ int tmp = 0; for (int i=1; i<count; i++){ tmp = array[i]; for (int j=i-1; j>=0; j--){ if (array[i] < array[j]){ array[j+1] = array[j]; } else{ array[j+1] = tmp; break; } } } } int main(int argc, char **argv){ if (argc < 2){ std::cout << argv[0] << " your_array" << std::endl; std::cout << "Example: " << argv[0] << " 1 3 2 4" << std::endl; exit(1); } if (argc > MaxArraySize){ std::cout << "Input Array too long!" << std::endl; } std::cout << argc << std::endl; std::cout << argv[1] << std::endl << std::endl; int ArraySize = argc - 1; int *Array = new int[MaxArraySize + 1]; memset(Array, 0, MaxArraySize + 1); std::cout << "Org order:" << std::endl; for (int i=1; i<argc; i++){ Array[i-1] = atoi(argv[i]); std::cout << Array[i-1] << " "; } std::cout << std::endl; InsertSortUp(Array, ArraySize); std::cout << "ascending order:" << std::endl; for (int i=0; i<ArraySize; i++){ std::cout << Array[i] << " "; } std::cout << std::endl; return 0; }

六、代码-链表实现方式

/************************************* Author: zchshen Date: 2017-07-25 Brief: ascending order of insert sort by link list(include head) **************************************/ #include <iostream> #include <stdlib.h> #include <stdint.h> #include <assert.h> using namespace std; typedef struct Node{ int data; struct Node* next; }LinkNode; void CreatListByEndInsert(LinkNode* head){ assert(head); head->next = NULL; LinkNode* Index = head; LinkNode* node; srand((uint32_t)time(NULL)); for (int i=0; i<20; i++){ try{ node = new LinkNode(); } catch(...){ return; } node->data = rand()%100; Index->next = node; Index = node; } node->next = NULL; } void DisPlayList(LinkNode* head){ assert(head); LinkNode* Index = head->next; while (NULL != Index){ cout << "Data: " << Index->data << endl; Index = Index->next; } cout << endl; } void ReleaseList(LinkNode* head){ assert(head); LinkNode* Index = head->next; while (NULL != Index){ delete Index; Index = NULL; } delete head; head = NULL; } void InsertSortUp(LinkNode* head){ assert(head); assert(head->next); LinkNode* curNode = head->next; LinkNode* frontNode = head; LinkNode* remainNode = curNode->next; LinkNode* insertNode = remainNode; curNode->next = NULL; while (remainNode){ while (NULL != curNode && insertNode->data >= curNode->data){ frontNode = curNode; curNode = curNode->next; } remainNode = remainNode->next; frontNode->next = insertNode; insertNode->next = curNode; insertNode = remainNode; curNode = head; frontNode = head; } } int main(int argc, char** argv){ LinkNode* head = NULL; try{ head = new LinkNode(); } catch(...){ exit(1); } CreatListByEndInsert(head); DisPlayList(head); InsertSortUp(head); DisPlayList(head); ReleaseList(head); return 0; }