C语言将数组写入到文件中的程序

现有一个整形数组a[6],先给数组a[6]由键盘赋值，然后将数组中元素值为奇数的元素值写入到啊a.txt文件中

#include<stdio.h>
void main{}
{
 FILE *fp
 int i,a[6];                 //i为数组元素下标

帮忙解答一下 谢谢

#include <stdio.h>
void main()
{
    FILE *fp;
    int i, a[6]; //i为数组元素下标
    fp = fopen("a.txt", "w");
    if (fp == NULL)
    {
        printf("Can't open the file!\n");
    }
    printf("请输入6个数：\n");
    for (i = 0; i < 6; i++)
    {
        scanf("%d", &a[i]);
        if (a[i] % 2 == 1)
            fprintf(fp, "%d ", a[i]);
    }
}

#include<stdio.h>
#include <stdlib.h>
void main()
{
    FILE* fp;
    int a[6];                 //i为数组元素下标
    if (fopen_s(&fp, "a.txt", "w+") != 0)
    {
        puts("Fail to open file!");
        return;
    }
    for (int i = 0; i < 6; i++)
    {
        scanf_s("%d", &a[i]);
        if (a[i] % 2 == 1)
        {
            fprintf(fp,"%d ",a[i]);
        }
    }
    fclose(fp);
    return;
}