#include <iostream>
#include <vector>
using namespace std;
 
int main(void){
  int N,M;
  cin>>N>>M;
  vector<int> A(N);
  for(int i = 0 ; i < N ; i ++)A[i] = i+1;
  for(int i = 0 ; i < M ; i ++){
    int num;
    cin>>num;
//    cout<<num<<endl;
    vector<int> now;
    num --;
    now.push_back(A[num]);
    
    for(int j = 0 ; j < num-1 ; j ++){
//      cout<<j+1<<" ";
      now.push_back(A[j]);
    }
    for(int j = num+1 ; j < N ; j ++){
//      cout<<j+1<<" ";
      now.push_back(A[j]);
    }
//    cout<<endl;
    for(int j = 0 ; j < now.size(); j++)
//      cout<<now[j]<<" ";
//    cout<<endl;cout<<endl;
    A = now;
    
  }
  cout<<A[0]<<endl;
}