#include <stdio.h>
#include<stdlib.h>

typedef struct node{
    struct node *prev;
    int data;
    struct node *next;
}Node;

Node *head=NULL,*tail;

void create(int num){
    Node *newNode = (Node*) malloc (1 * sizeof(Node));
    newNode->prev=NULL;
    newNode->next=NULL;
    newNode->data=num;
    if(head == NULL){
        head=newNode;
        tail=newNode;
    }
    else{
        newNode->prev=tail;
        tail->next=newNode;
        tail=newNode;
    }
    head->prev=tail;
    tail->next=head;
}

void display(int key){
    Node *itr,*ind;
    
    ind=head;
    int i;
    if(key<0){
        
        do{
            int sum=0;
            for(itr=ind->next,i=1;i<=key;itr=itr->next,i++){
                sum = sum+itr->next;
            }
            printf("%d",sum);
            ind = ind->next;
        }while(ind!=head);
    }
    else{
        do{
            int sum=0;
            for(itr=ind->prev,i=1;i<=key;itr=itr->prev,i++){
                sum = sum+itr->next;
            }
            printf("%d",sum);
            ind = ind->next;
        }while(ind!=head);
    }
}



int main() {
    int N,in,num,key;
    scanf("%d",&N);
    
    for(in=0;in<N;in++){
        scanf("%d",&num);
        create(num);
    }
    scanf("%d",&key);
    display(key);
}