#include <bits/stdc++.h>
using namespace std;
#define N 10000

typedef struct node {
    int flag;
    struct node* next;
}Node;

typedef struct ysf {
    int flag;
    struct ysf* next;
}Ysf;

Node* Create_node(int n) {
    Node* head = new Node;
    Node* cycle = NULL;
    head->flag = 1;
    head->next = NULL;
    cycle = head;
    for (int i = 2; i <= n; i++)
    {
        Node* p = new Node;
        p->flag = i;
        p->next = NULL;
        cycle->next = p;
        cycle = cycle->next;
    }
    cycle->next = head;
    return head;
}

Node* Create_ysf(int arr[], int r) {
    Node* head = new Node;
    Node* cycle = NULL;
    head->flag = arr[0];
    head->next = NULL;
    cycle = head;
    for (int i = 1; i < r; i++)
    {
        Node* p = new Node;
        p->flag = arr[i];
        p->next = NULL;
        cycle->next = p;
        cycle = cycle->next;
    }
    cycle->next = head;
    return head;
}

int n, m, arr[N];

void Output() {
    cin >> n >> m;
    Node* a = Create_node(n);
    for (int i = 0; i < m; i++)
        cin >> arr[i];
    Node* b = Create_ysf(arr, m);
    int t = 1;
    while (n > 1)
    {
        if (a->flag == 0)
            a = a->next;
        else
        {
            if (t == b->flag)
            {
                t = 1;
                a->flag = 0;
                b = b->next;
                a = a->next;
                n--;
            }
            else
            {
                t++;
                a = a->next;
            }
        }
    }
    while (a->flag == 0)
    {
        a = a->next;
    }
    cout << a->flag << endl;
}

int main() {
    Output();
    return 0;
}