#include <bits/stdc++.h>

using namespace std;

namespace {

    typedef double real;
    typedef long long ll;

    template<class T> ostream& operator<<(ostream& os, const vector<T>& vs) {
        if (vs.empty()) return os << "[]";
        auto i = vs.begin();
        os << "[" << *i;
        for (++i; i != vs.end(); ++i) os << " " << *i;
        return os << "]";
    }
    template<class T> istream& operator>>(istream& is, vector<T>& vs) {
        for (auto it = vs.begin(); it != vs.end(); it++) is >> *it;
        return is;
    }

    void input() {
    }

    void solve() {
        int N, M; cin >> N >> M;
        vector<int> xs;
        for (int i = 1; i <= N; i++) xs.push_back(i);
        for (int i = 0; i < M; i++) {
            int a; cin >> a; a--;
            int x = xs[a];
            vector<int> ys;
            ys.push_back(x);
            ys.insert(ys.end(), xs.begin(), xs.begin() + a);
            ys.insert(ys.end(), xs.begin() + a + 1, xs.end());
            xs = ys;
        }
        cout << xs[0] << endl;
    }
}

int main() {
    input(); solve();
    return 0;
}