#include <iostream>
#include <string>
#include <cmath>
#include <vector>

using namespace std;
#define REP(i,n) for (int i=0;i<(n);i++)
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define SWAP(a,b) (a ^= b,b = a ^ b,a ^= b)
#define IN(n) (cin >> n, n)


int main()
{
	int i, j, N, M, n, tmp;
	cin >> N >> M;
	int* v = new int[N + 1];
	for (i = 1; i <= N; i++) v[i] = i;
	for (i = 0; i < M; i++) {
		cin >> n; tmp = v[n];
		for (j = n; j > 1; j--) {
			v[j] = v[j - 1];
		}
		v[1] = tmp;
	}
	cout << v[1] << endl;

	delete[] v;
	return 0;
}