#include<stdio.h>
int h, w;
int kaiguan;
int main()
{
    int num;
    scanf("%d", &h);
    for (int j = 1; j <= h;j++)
    {
        kaiguan = 0;
        scanf("%d", &w);
        for (int i = 0; i < w; i++){
            scanf("%d", &num);
            if ((num == 1 && kaiguan == 1) || (num == 0 && kaiguan == 3))
                kaiguan = 2;
            else if (num == 0)
                kaiguan = 1;
            else if (num == 1)
                kaiguan = 3;
        }
        if (kaiguan == 2)
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}