174. 연결 리스트 머리 삽입과 노드 맨 앞 이동

1#include <stdio.h>
2#include <stdlib.h>
3 
4typedef struct Node {
5    int val;
6    struct Node *next;
7} Node;
8 
9int main() {
10    Node *head = NULL, *p, *prev;
11    int i;
12    for (i = 1; i <= 4; i++) {
13        p = (Node *)malloc(sizeof(Node));
14        p->val = i * 10;
15        p->next = head;
16        head = p;
17    }
18    prev = head;
19    while (prev->next->val != 20) {
20        prev = prev->next;
21    }
22    p = prev->next;
23    prev->next = p->next;
24    p->next = head;
25    head = p;
26    for (p = head; p != NULL; p = p->next) {
27        printf("[%d]", p->val);
28    }
29    printf("\n");
30    while (head != NULL) {
31        p = head;
32        head = head->next;
33        free(p);
34    }
35    return 0;
36}