#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int n, m, p, temp;
    cin >> n >> m;
    deque<int> d(n);
    for (int i = 1; i <= n; i++) d[i-1] = i;
    for (int i = 0; i < m; i++){
        cin >> p;
        temp = d[p-1];
        d.erase(d.begin() + p - 1);
        d.push_front(temp);
    }
    cout << d[0] << endl;
}