#include<stdio.h>
int main()
{
int n,i=1,cot=2,a,b,c=0,e;
printf("请输入一个大于等于3且小于等于7的数:");
scanf("%d",&n);
while(cot<=n){
i=i*10;
cot++;
}
i*10>e>=i;
for(a=i;a>1;a=a/10){
b= e/a;
c=b^n+c;
e%=i;
}
printf("%d",c);
return 0;
}