用c语言和链表写的爆栈了全re，才疏学浅，还不会c++

#include<stdio.h>
#include<stdlib.h>
typedef struct linklist {
    int loc;//存放位置
    long int data;//存的数据
    struct linklist* next;
}*Locker, node;

long int locnode(node* head, int a);
void renode(node* head, int n, long int m);
void addnode(node* head, int a, long int b);

int main() {
    int n, m;
    scanf("%d %d", &n, &m);
    node* locker = malloc(sizeof(Locker) * n);//分配数组存放每个柜子的头指针
    node* head = malloc(sizeof(Locker));
    head->next = NULL;

    for (int a = 1; a <= n; a++) {
        locker[a].next = head;
    }
    int x, i, j, k;
    long int out[10000];//存储查询的结果
    long int count = 0;//记录查询的次数
    while (m > 0) {

        scanf("%d ", &x);
        if (x == 1) {//做写入操作1
            scanf("%d %d %ld", &i, &j, &k);
            if (locnode(locker[i].next, j)) {//查找是否存在
                renode(locker[i].next, j, k);//存在，进行修改
            }
            else {
                addnode(locker[i].next, j, k);//不存在，插入新的结点
            }

        }
        else {//做读取操作2
            scanf("%d %d", &i, &j);
            out[count] = locnode(locker[i].next, j);//查找并返回
            count++;
        }
        m--;
    }
    for (int z = 0; z < count; z++) {
        printf("%ld\n", out[z]);
    }
    return 0;
}

long int locnode(node* head, int a) {
    node* Pnode = head->next;
    while (Pnode != NULL) {
        if (a == Pnode->loc) {
            return Pnode->data;
        }
        Pnode = Pnode->next;
    }
    return 0;
}

void renode(node* head, int n, long int m) {
    node* Pnode = head->next;
    while (Pnode != NULL) {
        if (n == Pnode->loc) {
            Pnode->data = m;
            break;
        }
        Pnode = Pnode->next;
    }
}

void addnode(node* head, int a, long int b) {
    node* spot = (node*)malloc(sizeof(node));
    node* p = head;

    while (p->next != NULL) {
        p = p->next;
    }
    spot->loc = a;
    spot->data = b;
    p->next = spot;
    spot->next = NULL;
}