c语言编程 有n个整数，使其前面各数顺序向后移动m个位置，最后m个数变成前面的m个数

#include <stdio.h>


int main()
{
int a[100];
int b[50];
int m,n,i;
int *p1,*p2;
p1=a;
p2=b;
printf("how many numbers:\n");
scanf("%d",&n);
printf("please enter %d numbers\n",n);
for (i=0;i<n;i++)
scanf("%d",&a[i]);
printf("how many digits :\n");
scanf("%d",&m);
for (p2=b,p1=a+m;p1<a+n;p2++,p1++)
{
*p2 = *p1;
}for (p1=a;p1<a+m;p1++)
{
*(p1+m)=*p1;
}
for (i=0;i<m;i++)
{
a[i]=b[i];
}
for (i=0;i<n;i++)
{
printf(a[i]);
}
    return 0;
}