#include<cstdio>
int main(){
	int n;
	scanf("%d",&n);
	int i,j,a[n+1],s[n+1];
	double q[n+1],t;
	for(i=1;i<=n;i++){
		scanf("%d",&a[i]);
		s[i]=i;
	}
	for(i=0;i<=n;i++){
		q[i]=0;
	}
	for(i=1;i<=n-1;i++){
		for(j=1;j<=n-i;j++){
			if(a[i]>a[i+1]){
				t=a[i];
				a[i]=a[i+1];
				a[i+1]=t;
				t=s[i];
				s[i]=s[i+1];
				s[i+1]=t;
			}
		}
	}
	for(i=1;i<=n;i++){
		q[i]=q[i-1]+a[i];
	}
	for(i=1;i<=n;i++){
		printf("%d ",s[i]);
	}
	t=q[n];
	printf("\n");
	printf("%.2lf",t/n);
}