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