菜鸟求助 输入三个字符串 并按由小到大的顺序输出 请高手帮忙看看我的程序哪里错了

#include"stdio.h"
#include"string.h"
#define N 3
void min_max(char *p[], int n)
{
int i, j, k;
char *a;
for (i = 0; i < n - 1; i++)
{
j = i;
for (k = i + 1; k < n; k++)
if (strcmp(p[j], p[k]) > 0)
j = k;
if (j != i)
{
a = p[i];
p[i] = p[j];
p[j] = a;
}
}
}
int main()
{
void min_max(char *p[], int n);
char *a[N];
int i;
printf("please input %d words:\n",N);
for (i = 0; i < N; i++)
scanf("%s", a[i]);
printf("The words are as follows:\n");
for (i = 0; i < N; i++)
printf("%s\n", a[i]);
min_max(a, N);
printf("Then, the words are as follows:\n");
for (i = 0; i < N; i++)
printf("%s\n", a[i]);
return 0;
}