修改字符数组中的元素时采样了指针，但发生访问冲突

Question

创建a1，a2，a3三个文件，向a1，a2中各输入五个字符，再将两组字符串合并并按ascll表排序后输入到a3，但在排序时发生访问冲突，不知道是数组越界还是指针出了问题，求指点！

#include <stdio.h>
#include <string.h>
int main()
{
    FILE *p1,*p2,*p3;
    int i,j;
    char b[2][10],*c;char p[10],(*c1)[10],m;c1=&p;c=&m;
    printf("file A:\n");
    gets(b[0]);
    printf("file B:\n");
    gets(b[1]);
    p1=fopen("a1","w");
    fputs(b[0],p1);
    fclose(p1);
    p2=fopen("a2","w");
    fputs(b[1],p2);
    fclose(p2);
    strcpy(p,b[0]);
    strcat(p,b[1]);
    //puts(c1);
    for(i=0;i<10;i++)
        for(j=i;i<n;j++)
        {
            if(p[j]<p[i]||p[j]==p[i])
            {
                *c=*(*c1+j);
                *(*c1+j)=*(*c1+i);
                *(*c1+i)=*c;
                
            }
        }
    printf("file C:\n");
    puts(p);
    putchar('\n');
    p3=fopen("a3","w");
    fputs(p,p3);
    fclose(p3);
}

Answer 1

#include <stdio.h>
#include <string.h>
int main()
{
    FILE* p1, * p2, * p3;
    int i, j=0;
    char b[2][10], * c; char p[11] = {0}, (*c1)[11], m; c1 = &p; c = &m; //p要申请11个空间，存放10个数据后应该为结束符预留一个位置，p要初始化为0
    printf("file A:\n");
    gets_s(b[0]);
    printf("file B:\n");
    gets_s(b[1]);
    p1 = fopen("a1", "w");
    fputs(b[0], p1);
    fclose(p1);
    p2 = fopen("a2", "w");
    fputs(b[1], p2);
    fclose(p2);
    strcpy(p, b[0]);
    strcat(p, b[1]);
    //puts(c1);
    for (i = 0; i < 10; i++)
        for (j = i; j < 10; j++)  //i改成j
        {
            if (p[j] < p[i] || p[j] == p[i])
            {
                *c = *(*c1 + j);
                *(*c1 + j) = *(*c1 + i);
                *(*c1 + i) = *c;
            }
        }
    printf("file C:\n");
    puts(p);
    putchar('\n');
    p3 = fopen("a3", "w");
    fputs(p, p3);
    fclose(p3);
}