12. 아래 코드에서 출력되는 값을 작성하시오.

struct Node {
    int value;
    struct Node* next;  
};

void func(struct Node* node) {
    while (node != NULL && node->next != NULL) {
        int t = node->value;
        node->value = node->next->value;
        node->next->value = t;
        node = node->next->next;
    }
}

int main() {
    struct Node n1 = {1, NULL};
    struct Node n2 = {2, NULL};
    struct Node n3 = {3, NULL};
    
    n1.next = &n3;  
    n3.next = &n2;

    func(&n1);

    struct Node* current = &n1;
    while (current != NULL) {
        printf("%d", current->value);  
        current = current->next;
    }
}