各种基本算法实现小结（一）—— 链 表

各种基本算法实现小结（一）—— 单链表

（均已测试通过）

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单链表(测试通过)

测试环境： Win-TC

#include <stdio.h> struct _node { int data; struct _node *next; }; typedef struct _node list; void display(list *l) { list *p; p=l; while(p->next) { printf("%5d", p->next->data); p=p->next; } } void main() { int i, n; list *h, *p, *s; printf("Enter num n:"); scanf("%d", &n); h=(list*)malloc(sizeof(list)); h->data=-1; h->next=NULL; s=p=h; for(i=n;i>0;i--) { p=(list*)malloc(sizeof(list)); scanf("%d", &(p->data)); p->next=h->next; h->next=p; h=h->next; } display(s); getch(); }

运行结果：

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单链表各种操作(测试通过)

测试环境： Win-TC

#include <stdio.h> #include <malloc.h> #include <stdlib.h> struct _node { int data; struct _node *next; }; typedef struct _node node, *plist; plist init_list() { plist pl; pl=(plist)malloc(sizeof(node)); if(NULL==pl) { printf("init list, malloc is fail.../n"); return NULL; } pl->data=-1; pl->next=NULL; return pl; } int isempty_list(plist pl) { if(NULL==pl || NULL!=pl->next) return 1; else return 0; } plist clear_list(plist pl) { pl=NULL; return pl; } void destroy_list(plist pl) { plist p, s; p=pl->next; while(p) { s=p; p=p->next; free(s); } pl=NULL; } void insert_item(plist pl, int i, int e) { int j=1; plist p, s; p=pl; while(p && j<i) { p=p->next; j++; } if(!p || j>i) /* >len or <1 */ printf("Insert fail.../n"); s=(plist)malloc(sizeof(node)); s->data=e; s->next=p->next; p->next=s; } void display(plist pl) { plist p; p=pl->next; while(pl && p) { printf("%5d", p->data); p=p->next; } printf("/n/n"); } int getbyid_item(plist pl, int i) { plist p=pl->next; int j=1; while(p && j<i) { p=p->next; j++; } if(!p || j>i) /* >len or <1 */ { printf("fail.../n"); exit(1); } return p->data; } int locate_item(plist pl, int e) { plist p=pl->next; int j=1; while(p->data != e && p->next) { p=p->next; j++; } if(p->data == e) return j; else { printf("There is n %d in list/n", e); return -1; } } void delete_item(plist pl, int i, int *e) { plist p=pl; plist q; int j=1; while(p->next && j<i) { p=p->next; j++; } if(!p->next || j>i) /* >len or <1 */ { printf("fail..../n"); return; } q=p->next; p->next=q->next; *e=q->data; free(q); } int len_list(plist pl) { int j=0; plist p=pl; while(pl && p->next) { j++; p=p->next; } return j; } plist traverse_list(plist pl) { plist h, p, s; if(!pl || !pl->next) return pl; h=pl->next; s=h; p=s->next; h->next=NULL; while(p) { s=p; p=p->next; s->next=h; h=s; } pl->next=h; return pl; } void main() { int len, pos, *del; plist pl=NULL; del=(int *)malloc(sizeof(int)); pl=init_list(); isempty_list(pl); insert_item(pl, 1, 1); insert_item(pl, 2, 3); insert_item(pl, 3, 5); insert_item(pl, 4, 7); insert_item(pl, 5, 9); insert_item(pl, 6, 11); display(pl); len=len_list(pl); printf("link list len: %d/n", len); pos=locate_item(pl, 7); printf("num 7 pos: %d/n", pos); delete_item(pl, 3, del); printf("delete pos 3 num: %d/n", *del); display(pl); printf("link list traverse.../n"); pl=traverse_list(pl); display(pl); destroy_list(pl); getch(); }

运行结果：

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单向循环链表(测试通过)

测试环境： Win-TC

#include <stdio.h> #include <malloc.h> struct _node { int data; struct _node *next; }; typedef struct _node node, *plist; plist init_list() { plist pl=(plist)malloc(sizeof(node)); if(!pl) { printf("error malloc fail.../n"); return NULL; } pl->data=-1; pl->next=pl; /* pl->next=NULL */ return pl; } void insert_item(plist pl, int pos, int data) { int j=0; plist p,s; s=p=pl; while(p && j<pos-1) { p=p->next; j++; } if(!p || j>pos-1) { printf("Error insert fail.../n"); return; } s=(plist)malloc(sizeof(node)); if(!s) { printf("Error malloc fail.../n"); return; } s->data=data; s->next=p->next; p->next=s; } int find_item(plist pl, int data) { plist s,p; s=p=pl; p=p->next; while(s != p) { if(data==p->data) return 1; p=p->next; } return 0; } void delete_item(plist pl, int data) { plist p,s; s=p=pl; if(data == p->data) /* first item is equal with data, then last item = second item */ { s=p; while(s != p->next) p=p->next; p->next=s->next; return; } while(s != p->next) /* first item is not equal with data */ { if(data == p->next->data) { p->next=p->next->next; return; } p=p->next; } } void display(plist pl) { plist s,p; s=p=pl; printf("%5d", p->data); /* print first item */ p=p->next; while(s != p) { printf("%5d", p->data); p=p->next; } printf("/n/n"); } void main() { int f; plist pl; pl=init_list(); insert_item(pl, 1, 1); insert_item(pl, 2, 3); insert_item(pl, 3, 5); insert_item(pl, 4, 7); insert_item(pl, 5, 9); display(pl); printf("Finding 3.../n"); f=find_item(pl, 3); if(f) printf("True find 3/n"); else printf("False find 3.../n"); printf("/nDeleting 1.../n"); delete_item(pl->next, 1); display(pl->next); getch(); }

运行结果：

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双向循环链表(测试通过)

测试环境： Win-TC

#include <stdio.h> #include <malloc.h> struct _node { int data; struct _node *prior; struct _node *next; }; typedef struct _node node, *plist; plist init_list() { plist p; p=(plist)malloc(sizeof(node)); if(!p) { printf("Error, malloc fail.../n"); return NULL; } p->data=-1; /* head->data = -1 */ p->prior=p; p->next=p; return p; } void insert_item(plist pl, int pos, int data) { int j=0; plist s,p; p=pl; while(p && j<pos-1) { p=p->next; j++; } if(!p || j>pos-1) /* pos is less than 1 or pos larger than len_list+1 */ { printf("Error %d is invalide num.../n", pos); return; } s=(plist)malloc(sizeof(node)); if(!s) { printf("Error, malloc fail.../n"); return NULL; } s->data=data; s->prior=p; s->next=p->next; p->next->prior=s; p->next=s; } int find_item(plist pl, int data) { plist s,p; s=p=pl; if(data == p->data) return 1; p=p->next; while(s != p) { if(data == p->data) return 1; p=p->next; } return 0; } void delete_item(plist pl, int data) { plist s,p; s=p=pl; if(data == p->data) /* first check equal */ { p->prior->next=p->next; p->next=p->prior; return; } while(s != p->next) { if(data == p->next->data) { p->next=p->next->next; p->next->next->prior=p; } p=p->next; } } void display(plist pl) { plist s,p; s=p=pl; printf("%5d", p->data); /* first item, such as head->data is -1 */ p=p->next; while(s != p) { printf("%5d", p->data); p=p->next; } printf("/n/n"); } void main() { int f; plist pl; pl=init_list(); insert_item(pl, 1, 1); insert_item(pl, 2, 3); insert_item(pl, 3, 5); insert_item(pl, 4, 7); insert_item(pl, 5, 9); display(pl); printf("Finding 3.../n"); f=find_item(pl->next->next, 3); if(f) printf("True find 3/n"); else printf("Fail find 3.../n"); printf("Finding 6.../n"); f=find_item(pl->prior->prior, 6); if(f) printf("True find 6/n"); else printf("Fail find 6.../n"); printf("/nDeleting 3.../n"); delete_item(pl->next->next, 3); display(pl); getch(); }

运行结果：

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以上代码，均在Win-TC 1.9.1 编译器环境测试通过（测试部分用例）

由于刚刚学习算法，编程水平有限，以上代码多有考虑不周或错误

欢迎大家在下面留言，改正或优化代码，给予指点或建议，谢谢！

参考推荐：

学习算法之路

各种基本算法实现小结（一）—— 链 表

各种基本算法实现小结（二）—— 堆 栈

各种基本算法实现小结（三）—— 树与二叉树

各种基本算法实现小结（四）—— 图及其遍历

各种基本算法实现小结（五）—— 排序算法

各种基本算法实现小结（六）—— 查找算法

各种基本算法实现小结（七）—— 常用算法

12个有趣的C语言面试题