Linked List Demo

Modified

2025-10-12

原始 C 程序

```{.c} #include <stdio.h> #include <stdlib.h> #include <string.h>

// … 这里粘贴完整的 Linkedlist.c 代码 … #include <stdio.h> #include <stdlib.h> #include <string.h>

typedef struct Node { char name[32]; struct Node *next; } Node;

/* 在链表尾部插入 name，返回“新的尾结点” / Node push_back(Node last, const char name) { Node p = (Node)malloc(sizeof(Node)); if (!p) { perror(“malloc”); exit(1); }

strncpy(p->name, name, sizeof(p->name)-1);
p->name[sizeof(p->name)-1] = '\0';
p->next = NULL;

if (last) {               // 不是第一个节点：把它接在尾巴后
    last->next = p;
}
return p;                 // 返回新的“尾结点”

}

/* 打印链表 / void print_list(Node head) { for (Node *cur = head; cur; cur = cur->next) { printf(“%s%s”, cur->name, cur->next ? ” -> ” : ” -> null“); } }

/* 统计节点数 / int count(Node h) { int numberofnodes = 0; for (Node *p = h; p != NULL; p = p->next) { numberofnodes++; } return numberofnodes; }

int main(void) { Node head = NULL; Node tail = NULL;

// 构造图里的初始链表：Jacob -> Joseph -> Mary
tail = push_back(NULL, "Jacob");  // 第一个节点
head = tail;                      // 记录头指针
tail = push_back(tail, "Joseph"); // 接在尾部
tail = push_back(tail, "Mary");

print_list(head);
printf("This linked list has %d nodes.\n\n", count(head));

// 在末尾插入 Ann（对应 Fig. 3.6 第二行）
tail = push_back(tail, "Ann");

print_list(head);
printf("This linked list has %d nodes.\n", count(head));

return 0;

}