其实思路很简单，和“删除元素”这道题一样，使用假插入即可

#include<bits/stdc++.h>
using namespace std;
int n,a[11],x,y;
int main(){
	scanf("%d",&n);
	for(int i = 1;i<=n;i++)scanf("%d",&a[i]);
	scanf("%d%d",&x,&y);
	for(int i = 1;i<=n;i++)
		if(i == x)printf("%d %d ",y,a[i]);
		else printf("%d ",a[i]);
    return 0;
}