C++ 排序双向循环链表代码

#include "LinkedList.h" #include<string.h> using namespace std; LinkedList::LinkedList(int memory){ this->memory = memory; first= new struct Stu; first->next = first; first->pre = first; } LinkedList::~LinkedList(){ } int LinkedList::insert(LkItem item){ //Full Check! :: Error Message (-1). if(isFull()) return -1; //Distrubute Memory to Stu struct. Stu *inStu = new struct Stu; inStu->item = item; //Search and Insert. if(direction(item.name) == 1){ search(item.name,-1); inStu->next = location; inStu->pre = location->pre; location->pre->next = inStu; location->pre = inStu; } else{ search(item.name,1); inStu->pre = location; inStu ->next = location->next; location->next->pre = inStu; location->next = inStu; } --memory; return 1; } int LinkedList::get(string name,LkItem& item){ //If Search-Funtion returns 0 value, it means already found. if(search(name,0)==0){ item = location->item; return 1; } return 0; } int LinkedList::remove(string name,LkItem& item){ int result = 0; //If Search-Funtion returns 0 value, it means already found. if(search(name,0)==0){ item = location->item; Stu *temp = location; location = location->next; location->pre = temp->pre; temp->pre->next = location; delete temp; result = 1; } return result; } int LinkedList::direction(string insert_Name){ if(insert_Name[0]<='L' || insert_Name[0]<='l' && insert_Name[0]>='A' || insert_Name[0]>='a') return 1; else return -1; } int LinkedList::search(string insert_Name,int value){ goFirst(); string current_Name; int insert_drection = -2; // insert_drection value: // 0 ----- insert_Name == current_Name ( can use in Fuction get() and remove() ) // 1 ----- insert_Name insert backward // -1 ----- insert_Name insert forward do{ if(direction(insert_Name)== 1) location = location->next; else location = location->pre; current_Name = location->item.name; if(strcmp(insert_Name.c_str(),current_Name.c_str()) == 0) insert_drection = 0; else if(strcmpi(insert_Name.c_str(),current_Name.c_str()) > 0) insert_drection = 1; else if(strcmpi(insert_Name.c_str(),current_Name.c_str()) < 0) insert_drection = -1; if(insert_drection == value) break; }while(!(location == first)); return insert_drection; } int LinkedList::next(LkItem& item){ if(isEmpty()||location->next == first) return 0; location = location->next; item = location->item; return 1; } int LinkedList::back(LkItem &item){ if(isEmpty()||location->pre == first) return 0; location = location->pre; item = location->item; return 1; } void LinkedList::makeEmpty(){ goFirst(); while(!(location->next == first)){ next(location->item); Stu *temp; temp = location; location = location->next; location->pre = temp->pre; temp->pre->next = location; delete temp; } } bool LinkedList::isFull(){ if(memory <= 0) return true; return false; } bool LinkedList::isEmpty(){ if(first->pre == first) return true; return false; } void LinkedList::goFirst(){ location = first; }