#include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <iomanip>
#include <algorithm>
using namespace std;
using ll = long long;

int main() {
    int N, M;
    cin >> N >> M;
    vector<int> v(N);
    for(int i=0; i<N; ++i) {
        v[i] = i+1;
    }
    for(int i=0; i<M; ++i) {
        int a;
        cin >> a;
        a--;
        int t = v[a];
        for(int j=a; j>=1; --j) {
            v[j] = v[j-1];
        }
        v[0] = t;
    }
    cout << v[0] << endl;
}