/*/?? - ?????   
 
?? ??-From Whf 
?? 
?? n ???????????????????????????????????????????????????????????????????n ???300 
????6???3?6?7?1?5?4????? 26/6=4.33?? 1 ??????
 
???? 
?1????????? n? 
?2???? n ?????????????? 

 
???? 
???????????????????????????????????????????????????
 
???? 
7
1 2 3 4 5 6 7
 
???? 
1,7
 
/*/
void main(){
	int n,a[300],sum=0,i,j,temp,sign=0;
	float p,dis;
	scanf("%d",&n);
	for(i=0;i<n;i++){
		scanf("%d",&a[i]);
		sum=sum+a[i];
	}
	p=(float)(sum)/n;
	for(i=0;i<n;i++){
		for(j=0;j<n-1-i;j++){
			if(a[j]>a[j+1]){
				temp=a[j];
				a[j]=a[j+1];
				a[j+1]=temp;
			}
		}
	}
	//printf("%f",p);
	if(p-(float)a[0]==(float)a[n-1]-p){
		for(i=0;i<n;i++){
			if(a[i]==a[0])
				if(sign==0){
					printf("%d",a[i]);
					sign=1;
				}
				else{
					printf(",%d",a[i]);
					
				}
			if(a[i]==a[n-1])
				if(sign==0){
					printf("%d",a[i]);
					sign=1;
				}
				else{
					printf(",%d",a[i]);
					sign=1;
				}
		}
	}
	else {
		if(p-(float)a[0]>(float)a[n-1]-p){
		dis=p-(float)a[0];
		printf("%d",a[0]);
		sign=0;
	}
	else{
		dis=(float)a[n-1]-p;
		sign=1;
	}
	//printf("%f",dis);
	for(i=0;i<n;i++){
		if(sign==0&&i==0||sign==1&&i==n-1)
			continue;
		if(sign==0&&a[i]==a[0]){
			printf(",%d",a[i]);	
		}
		else if(sign==1&&a[i]==a[n-1]){
				printf("%d,",a[i]);	
		}
	}
	if(sign==1)
		printf("%d",a[n-1]);
	}
}