可变长度结构体

//
// Created by liu on 2020/10/7.
//

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>struct Node {
    int id;
    int *data;
};

#define case1

int main() {

#ifdef   case1
    int DataSize = 10;
    struct Node node;
    node.data = (int *) malloc(sizeof(int) * DataSize);
    node.data[0] = 1;
    node.data[1] = 5;
    for (int i = 0; i < 10; i++) {
        printf("node.data[%d]:%d\n", i, node.data[i]);
    }
#endif

#ifdef case2
    int DataSize  = 10;
    int data[DataSize];
    struct Node  node;
    node.data = data;
    node.data[0] = 10;
    node.data[1] = 50;
    for (int i = 0; i < DataSize; i++) {
        printf("node.data[%d]:%d\n",i ,node.data[i]);
    }

#endif

#ifdef case3
    int DataSize  = 10;
    struct Node * node =  (struct Node *)malloc(sizeof(struct Node) + DataSize);
    node->data = node + sizeof(struct Node);
    node->data[0] = 100;
    node->data[1] = 500;
    for (int i = 0; i < DataSize; i++) {
        printf("node.data[%d]:%d\n",i ,node->data[i]);
    }
#endif


    return 0;
}