#include <stdio.h>

int main(void)
{
	int flag, i, n, x;
	int looptimes, ri;
	int a[10];

	scanf("%d", &looptimes);
	for (ri = 1; ri <= looptimes; ++ri) {
		scanf("%d", &n);
		for (i = 0; i < n; ++i) {
			scanf("%d", &a[i]);
		}
		scanf("%d", &x);
		flag = 0;
		for (i = 0; i < n; ++i) {
			if (a[i] == x) {
				flag = 1;
				break;
			}
		}
		if (flag != 0) {
			printf( "%d: a[%d]\n", x, i);
		} else {
			printf( "%d: not found\n", x);
		}
	}
	return 0;
}