#include <stdio.h>

#define N 50

int main(int argc, const char * argv[]) {
  int card[N], n, m, a, temp;

  scanf("%d %d", &n, &m);

  for (a = 0; a < n; a++)
    card[a] = a + 1;

  for (; m > 0; m--) {
    scanf("%d", &a);
    temp = card[--a];
    for (; a > 0; a--)
      card[a] = card[a - 1];
    card[0] = temp;
  }

  printf("%d\n", card[0]);

  return 0;
}