#include <stdio.h>

int main() {
    int n, m;
    scanf("%d%d", &n, &m);
    int a[m];
    for (int i = 0; i < m; ++i) scanf("%d", &a[i]);
    int cards[n + 1], work[n + 1];
    for (int i = 0; i < n; ++i) cards[i] = i + 1;
    for (int i = 0; i < m; ++i) {
        int j = a[i] - 1;
        work[0] = cards[j];
        for (int k = 0; k < j; ++k) work[k + 1] = cards[k];
        for (int k = j; k <= n; ++k) work[k] = cards[k];
        for (int k = 0; k <= n; ++k) cards[k] = work[k];
    }
    printf("%d\n", cards[0]);
    return 0;
}