#include <iostream>
#include <vector>
#include <list>
#include <deque>
#include <map>
#include <algorithm>
#include <cmath>

using namespace std;

#define FOR(x,y) for(int x = 0;x < y;x++)
#define LLI long long int

template<int um> class UF {
public:
    vector<int> par,rank,cnt;
    UF() {par=rank=vector<int>(um,0); cnt=vector<int>(um,1); for(int i=0;i<um;i++) par[i]=i;}
    void reinit() {FOR(i,um) rank[i]=0,cnt[i]=1,par[i]=i;}
    int operator[](int x) {return (par[x]==x)?(x):(par[x] = operator[](par[x]));}
    int count(int x) { return cnt[operator[](x)];}
    int operator()(int x,int y) {
        if((x=operator[](x))==(y=operator[](y))) return x;
        cnt[y]=cnt[x]=cnt[x]+cnt[y];
        if(rank[x]>rank[y]) return par[x]=y;
        rank[x]+=rank[x]==rank[y]; return par[y]=x;
    }
};

int main() {
    int n,m;
    cin >> n >> m;
    vector<int> shuffle(m);
    FOR(i, m)
    {
        cin >> shuffle[i];
    }
    deque<int> data(n);
    FOR(i, n)
    {
        data[i] = i + 1;
    }
    
    FOR(i, m)
    {
        int index = shuffle[i]-1;
        int target = data[index];
        data.erase(data.begin() + index);
        data.push_front(target);
    }
    cout << data.front() << endl;
    return 0;
}