#include <stdio.h>

int main() {
	int n, m, a, card[50], t, i, j;

	scanf("%d %d", &n, &m);
	for (i = 0; i < n; i++) {
		card[i] = i + 1;
	}
	for (i = 0; i < m; i++) {
		scanf("%d", &a);
		t = card[a - 1];
		for (j = a - 1; j > 0; j--) {
			card[j] = card[j - 1];
		}
		card[0] = t;
	}

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