求能把数据保存到文件的功能，和最后把链表释放

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define PATH "baocun"
typedef struct SPB
{
int seller_num;
int fit_num;
int building_num;
int count;
struct SPB* next;
} ListNode, * LinkList;
int main()
{ int i;
struct SPB* head = (struct SPB*)malloc(sizeof(struct SPB));
if (head == NULL)
{
printf("分配失败，程序结束");
exit(0);
}
head->next = NULL;
struct SPB* p = NULL;
p=head;
int ch = 0;
while (ch != 7)
{
printf("\nMUNU\n");//菜单
printf("add data---------1\n"); //增加
printf("delete data------2\n"); //删除
printf("update data------3\n"); //修改
printf("insert data------4\n"); //插入
printf("print linklist---5\n"); //输出
printf("baocun-----------6\n"); //保存
printf("exit ------------7\n"); //退出
printf("***********\n\n");
printf("请输入你的选择:");
scanf("%d", &ch);
if (ch == 1)
{
struct SPB pb; //struct SPB pf, * pb;
int i;
if (head == NULL)
continue;
else {
p = head;
while (p->next) p = p->next;
}
for (i = 0; i < 2; i++)
{
pb = (struct SPB*)malloc(sizeof(struct SPB));
if (NULL == pb)
{
printf("malloc fail!\n");
break; //return head;
}
pb->next = NULL;
printf("\nseller's number: ");
scanf("%d", &pb->seller_num);
printf("fit's number: ");
scanf("%d", &pb->fit_num);
printf("builiding's number: ");
scanf("%d", &pb->building_num);
printf("count's number: ");
scanf("%d", &pb->count);
p->next = pb;
p = pb;
}
}if (ch == 2)
{
int i, j = 0;
struct SPB q = NULL;
if (head == NULL)
continue;
else {
p = head;
}
do {
printf("请输入需删除的项:");
scanf("%d", &i);
} while (i <= 0);
while (p && j < i)
{
q = p;
p = p->next;
j++;
}
if (p == NULL)
printf("\n未找到删除的项.\n");
else {
q->next = p->next;
free(p);
printf("\n第%d项删除成功.\n", i);
}
}
if (ch == 3)
{
int i, j = 0;
if (head == NULL)
continue;
else {
p = head;
}
do {
printf("请输入需修改的项:");
scanf("%d", &i);
} while (i <= 0);
while (p && j < i)
{
p = p->next;
j++;
}
if (p == NULL)
printf("\n未找到修改的项.\n");
else {
int sel;
do {
printf("\n请输入你要修改的数据 1,销售商号码 2,配件号 3,工地号 4,数量 :");
scanf("%d", &sel);
} while (sel < 1 || sel>4);
switch (sel) {
case 1:
printf("请输入新的销售商品号：");
scanf("%d", &p->seller_num);
break;
case 2:
printf("请输入新的配件号：");
scanf("%d", &p->fit_num);
break;
case 3:
printf("请输入新的工地号：");
scanf("%d", &p->building_num);
break;
case 4:
printf("请输入新的数量：");
scanf("%d", &p->count);
break;
default:
break;
}
printf("\n第%d项数据修改成功.\n", i);
}
}
if (ch == 4)
{
int i, j = 0;
if (head == NULL)
continue;
else {
p = head;
}
struct SPB q = NULL, * ib = (struct SPB)malloc(sizeof(struct SPB));
ib->next = NULL;
do {
printf("请输入插入的项序号（前插）:");
scanf("%d", &i);
} while (i <= 0);
printf("\n请输入插入项的数据:\n");
printf("\nseller's number: ");
scanf("%d", &ib->seller_num);
printf("fit's number: ");
scanf("%d", &ib->fit_num);
printf("builiding's number: ");
scanf("%d", &ib->building_num);
printf("count's number: ");
scanf("%d", &ib->count);
while (p && j < i)
{
q = p;
p = p->next;
j++;
}
if (p == NULL)
q->next = ib;
else {
ib->next = q->next;
q->next = ib;
}
printf("\n第%d项插入成功.\n", i);
}
if (ch == 5)
{
if (head->next == NULL)
continue;
else {
p = head->next;
}
printf("\n1.销售商号码\t2.配件号\t3.工地号\t4.数量\n");
while (p)
{
printf("%d\t\t%d\t\t%d\t\t%d\n", p->seller_num, p->fit_num, p->building_num, p->count);
p = p->next;
}
}
}
if(ch==6)
{
if (head == NULL)
{
printf("节点为空，保存失败\n%s\t%d\t%s\n", FILE, LINE, func);
}
//打开文件
FILE fp = fopen(PATH, "w");
if (fp == NULL)
{
printf("打开文件失败\n");
}
//保存操作
struct SPB bc = head->next;
while (bc != NULL)
{
fprintf(fp,"%d",bc->seller_num);
fprintf(fp,"%d",bc->fit_num);
fprintf(fp,"%d",bc->fit_num);
fprintf(fp,"%d",bc->building_num);
fprintf(fp,"%d",bc->count);
bc = bc->next;
}
//收尾处理
fclose(fp);
fp = NULL;
printf("保存成功");
}
return 0;
free(p);
}

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define PATH "baocun"
typedef struct SPB
{
    int seller_num;
    int fit_num;
    int building_num;
    int count;
    struct SPB *next;
} ListNode, *LinkList;

int main()
{
    int i;
    struct SPB *head = (struct SPB *)malloc(sizeof(struct SPB));
    if (head == NULL)
    {
        printf("分配失败，程序结束");
        exit(0);
    }
    head->next = NULL;
    struct SPB *p = NULL;
    p = head;
    int ch = 0;
    while (ch != 7)
    {
        printf("\nMUNU\n");             //菜单
        printf("add data---------1\n"); //增加
        printf("delete data------2\n"); //删除
        printf("update data------3\n"); //修改
        printf("insert data------4\n"); //插入
        printf("print linklist---5\n"); //输出
        printf("baocun-----------6\n"); //保存
        printf("exit ------------7\n"); //退出
        printf("***********\n\n");
        printf("请输入你的选择:");
        scanf("%d", &ch);
        if (ch == 1)
        {
            struct SPB *pb; //struct SPB pf, * pb;
            int i;
            if (head == NULL)
                continue;
            else
            {
                p = head;
                while (p->next)
                    p = p->next;
            }
            for (i = 0; i < 2; i++)
            {
                pb = (struct SPB *)malloc(sizeof(struct SPB));
                if (NULL == pb)
                {
                    printf("malloc fail!\n");
                    break; //return head;
                }
                pb->next = NULL;
                printf("\nseller's number: ");
                scanf("%d", &pb->seller_num);
                printf("fit's number: ");
                scanf("%d", &pb->fit_num);
                printf("builiding's number: ");
                scanf("%d", &pb->building_num);
                printf("count's number: ");
                scanf("%d", &pb->count);
                p->next = pb;
                p = pb;
            }
        }
        if (ch == 2)
        {
            int i, j = 0;
            struct SPB *q = NULL;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            do
            {
                printf("请输入需删除的项:");
                scanf("%d", &i);
            } while (i <= 0);
            while (p && j < i)
            {
                q = p;
                p = p->next;
                j++;
            }
            if (p == NULL)
                printf("\n未找到删除的项.\n");
            else
            {
                q->next = p->next;
                free(p);
                printf("\n第%d项删除成功.\n", i);
            }
        }
        if (ch == 3)
        {
            int i, j = 0;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            do
            {
                printf("请输入需修改的项:");
                scanf("%d", &i);
            } while (i <= 0);
            while (p && j < i)
            {
                p = p->next;
                j++;
            }
            if (p == NULL)
                printf("\n未找到修改的项.\n");
            else
            {
                int sel;
                do
                {
                    printf("\n请输入你要修改的数据 1,销售商号码 2,配件号 3,工地号 4,数量 :");
                    scanf("%d", &sel);
                } while (sel < 1 || sel > 4);
                switch (sel)
                {
                case 1:
                    printf("请输入新的销售商品号：");
                    scanf("%d", &p->seller_num);
                    break;
                case 2:
                    printf("请输入新的配件号：");
                    scanf("%d", &p->fit_num);
                    break;
                case 3:
                    printf("请输入新的工地号：");
                    scanf("%d", &p->building_num);
                    break;
                case 4:
                    printf("请输入新的数量：");
                    scanf("%d", &p->count);
                    break;
                default:
                    break;
                }
                printf("\n第%d项数据修改成功.\n", i);
            }
        }
        if (ch == 4)
        {
            int i, j = 0;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            struct SPB *q = NULL, *ib = (struct SPB *)malloc(sizeof(struct SPB));
            ib->next = NULL;
            do
            {
                printf("请输入插入的项序号（前插）:");
                scanf("%d", &i);
            } while (i <= 0);
            printf("\n请输入插入项的数据:\n");
            printf("\nseller's number: ");
            scanf("%d", &ib->seller_num);
            printf("fit's number: ");
            scanf("%d", &ib->fit_num);
            printf("builiding's number: ");
            scanf("%d", &ib->building_num);
            printf("count's number: ");
            scanf("%d", &ib->count);
            while (p && j < i)
            {
                q = p;
                p = p->next;
                j++;
            }
            if (p == NULL)
                q->next = ib;
            else
            {
                ib->next = q->next;
                q->next = ib;
            }
            printf("\n第%d项插入成功.\n", i);
        }
        if (ch == 5)
        {
            if (head->next == NULL)
                continue;
            else
            {
                p = head->next;
            }
            printf("\n1.销售商号码\t2.配件号\t3.工地号\t4.数量\n");
            while (p)
            {
                printf("%d\t\t%d\t\t%d\t\t%d\n", p->seller_num, p->fit_num, p->building_num, p->count);
                p = p->next;
            }
        }
        if (ch == 6)
        {
            if (head == NULL)
            {
                printf("节点为空，保存失败\n%s\t%d\t%s\n", __FILE__, __LINE__, __func__);
            }
            //打开文件
            FILE *fp = fopen(PATH, "w");
            if (fp == NULL)
            {
                printf("打开文件失败\n");
                continue;
            }
            //保存操作
            struct SPB *bc = head->next;
            while (bc != NULL)
            {
                fprintf(fp, "%d ", bc->seller_num);
                fprintf(fp, "%d ", bc->fit_num);
                fprintf(fp, "%d ", bc->fit_num);
                fprintf(fp, "%d ", bc->building_num);
                fprintf(fp, "%d ", bc->count);
                fprintf(fp, "\n");
                bc = bc->next;
            }
            //收尾处理
            fclose(fp);
            fp = NULL;
            printf("保存成功");
        }
    }
    // 释放操作
    p = head;
    while (p) {
        struct  SPB *q = p->next;
        free(p);
        p = q;
    }
    return 0;
}

其实问题不大，主要是ch == 6写在了while的外面

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define PATH "baocun"
typedef struct SPB
{
    int seller_num;
    int fit_num;
    int building_num;
    int count;
    struct SPB *next;
} ListNode, *LinkList;
int main()
{
    int i;
    struct SPB *head = (struct SPB *)malloc(sizeof(struct SPB));
    if (head == NULL)
    {
        printf("分配失败，程序结束");
        exit(0);
    }
    head->next = NULL;
    struct SPB *p = NULL;
    p = head;
    int ch = 0;
    while (ch != 7)
    {
        printf("\nMUNU\n");             //菜单
        printf("add data---------1\n"); //增加
        printf("delete data------2\n"); //删除
        printf("update data------3\n"); //修改
        printf("insert data------4\n"); //插入
        printf("print linklist---5\n"); //输出
        printf("baocun-----------6\n"); //保存
        printf("exit ------------7\n"); //退出
        printf("***********\n\n");
        printf("请输入你的选择:");
        scanf("%d", &ch);
        if (ch == 1)
        {
            struct SPB *pb; //struct SPB pf, * pb;
            int i;
            if (head == NULL)
                continue;
            else
            {
                p = head;
                while (p->next)
                    p = p->next;
            }
            for (i = 0; i < 2; i++)
            {
                pb = (struct SPB *)malloc(sizeof(struct SPB));
                if (NULL == pb)
                {
                    printf("malloc fail!\n");
                    break; //return head;
                }
                pb->next = NULL;
                printf("\nseller's number: ");
                scanf("%d", &pb->seller_num);
                printf("fit's number: ");
                scanf("%d", &pb->fit_num);
                printf("builiding's number: ");
                scanf("%d", &pb->building_num);
                printf("count's number: ");
                scanf("%d", &pb->count);
                p->next = pb;
                p = pb;
            }
        }
        if (ch == 2)
        {
            int i, j = 0;
            struct SPB *q = NULL;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            do
            {
                printf("请输入需删除的项:");
                scanf("%d", &i);
            } while (i <= 0);
            while (p && j < i)
            {
                q = p;
                p = p->next;
                j++;
            }
            if (p == NULL)
                printf("\n未找到删除的项.\n");
            else
            {
                q->next = p->next;
                free(p);
                printf("\n第%d项删除成功.\n", i);
            }
        }
        if (ch == 3)
        {
            int i, j = 0;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            do
            {
                printf("请输入需修改的项:");
                scanf("%d", &i);
            } while (i <= 0);
            while (p && j < i)
            {
                p = p->next;
                j++;
            }
            if (p == NULL)
                printf("\n未找到修改的项.\n");
            else
            {
                int sel;
                do
                {
                    printf("\n请输入你要修改的数据 1,销售商号码 2,配件号 3,工地号 4,数量 :");
                    scanf("%d", &sel);
                } while (sel < 1 || sel > 4);
                switch (sel)
                {
                case 1:
                    printf("请输入新的销售商品号：");
                    scanf("%d", &p->seller_num);
                    break;
                case 2:
                    printf("请输入新的配件号：");
                    scanf("%d", &p->fit_num);
                    break;
                case 3:
                    printf("请输入新的工地号：");
                    scanf("%d", &p->building_num);
                    break;
                case 4:
                    printf("请输入新的数量：");
                    scanf("%d", &p->count);
                    break;
                default:
                    break;
                }
                printf("\n第%d项数据修改成功.\n", i);
            }
        }
        if (ch == 4)
        {
            int i, j = 0;
            if (head == NULL)
                continue;
            else
            {
                p = head;
            }
            struct SPB *q = NULL, *ib = (struct SPB *)malloc(sizeof(struct SPB));
            ib->next = NULL;
            do
            {
                printf("请输入插入的项序号（前插）:");
                scanf("%d", &i);
            } while (i <= 0);
            printf("\n请输入插入项的数据:\n");
            printf("\nseller's number: ");
            scanf("%d", &ib->seller_num);
            printf("fit's number: ");
            scanf("%d", &ib->fit_num);
            printf("builiding's number: ");
            scanf("%d", &ib->building_num);
            printf("count's number: ");
            scanf("%d", &ib->count);
            while (p && j < i)
            {
                q = p;
                p = p->next;
                j++;
            }
            if (p == NULL)
                q->next = ib;
            else
            {
                ib->next = q->next;
                q->next = ib;
            }
            printf("\n第%d项插入成功.\n", i);
        }
        if (ch == 5)
        {
            if (head->next == NULL)
                continue;
            else
            {
                p = head->next;
            }
            printf("\n1.销售商号码\t2.配件号\t3.工地号\t4.数量\n");
            while (p)
            {
                printf("%d\t\t%d\t\t%d\t\t%d\n", p->seller_num, p->fit_num, p->building_num, p->count);
                p = p->next;
            }
        }
        if (ch == 6)
        {
            if (head == NULL)
            {
                printf("节点为空，保存失败\n");
            }
            //打开文件
            FILE *fp = fopen("a.txt", "w");
            if (fp == NULL)
            {
                printf("打开文件失败\n");
            }
            //保存操作
            struct SPB *bc = head->next;
            while (bc != NULL)
            {
                fprintf(fp, "%d", bc->seller_num);
                fprintf(fp, "%d", bc->fit_num);
                fprintf(fp, "%d", bc->building_num);
                fprintf(fp, "%d", bc->count);
                fprintf(fp,"\n");
                bc = bc->next;
            }
            //收尾处理
            fclose(fp);
            fp = NULL;
            printf("保存成功");
        }
    }

    return 0;
    free(p);
}