在C中创建二维链表

Question

对于赋值，我们必须在C中实现一个二维链表。 我的想法是自己创建几个链接列表，并将其头部链接在一起。

这是我想出的代码，不幸的是它无法正常工作。 当我尝试从树节点开始遍历结果时，没有打印任何内容。

有人能指出正确的方向吗？

#include <stdio.h>
#include <stdlib.h>

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

struct head {
   int value;
   struct head *next;
   struct cell *cells;
};

struct head *current_head, *new_head;
struct cell *current_cell, *new_cell;

int i;
int j;
void grid_init(int num_rows,int num_columns){
    for (i=0; i<num_rows-1;i++) {
        struct cell * current_cell = (struct cell* ) malloc (sizeof(struct cell));
        current_head->cells = current_cell;
        for (j=0; j<num_columns-1; j++) {
            struct cell* new_cell = (struct cell* ) malloc (sizeof(struct cell));
            current_cell->next = new_cell;
            current_cell->value=j;
            current_cell = new_cell;
        }
        struct head* new_head = (struct head *) malloc (sizeof(struct head));
        current_head->next = new_head;
        current_head->value=i;
        current_head = new_head;
    }
};



void print_grid(){
    struct head* temp = current_head;
    struct cell* tempcell = current_cell;
    while(temp->next!=NULL){
        tempcell = temp->cells;
        while(tempcell->next!=NULL){
            tempcell = temp->cells;
            printf("%i", tempcell->value);
            tempcell = tempcell->next;
        }
        temp = temp->next;
    }
};

int main(){
    current_head = (struct head *) malloc (sizeof(struct head));
    int a=5;
    int b=5;
    grid_init(a,b);
    print_grid();
};