CF1746A.Maxmina

You have an array $a$ of size $n$ consisting only of zeroes and ones and an integer $k$ . In one operation you can do one of the following:

• Select $2$ consecutive elements of $a$ and replace them with their minimum (that is, let $a := [a_{1}, a_{2}, \ldots, a_{i-1}, \min(a_{i}, a_{i+1}), a_{i+2}, \ldots, a_{n}]$ for some $1 \le i \le n-1$ ). This operation decreases the size of $a$ by $1$ .
• Select $k$ consecutive elements of $a$ and replace them with their maximum (that is, let $a := [a_{1}, a_{2}, \ldots, a_{i-1}, \max(a_{i}, a_{i+1}, \ldots, a_{i+k-1}), a_{i+k}, \ldots, a_{n}]$ for some $1 \le i \le n-k+1$ ). This operation decreases the size of $a$ by $k-1$ .

Determine if it's possible to turn $a$ into $[1]$ after several (possibly zero) operations.

Each test contains multiple test cases. The first line contains the number of test cases $t$ ( $1 \le t \le 1000$ ). The description of the test cases follows.

The first line of each test case contains two integers $n$ and $k$ ( $2 \le k \le n \le 50$ ), the size of array $a$ and the length of segments that you can perform second type operation on.

The second line contains $n$ integers $a_{1}, a_{2}, \ldots, a_{n}$ ( $a_i$ is $0$ or $1$ ), elements of array $a$ .

For each test case, if it is possible to turn $a$ into $[1]$ , print "YES", otherwise print "NO".

In the first test case, you can perform the second type operation on second and third elements so $a$ becomes $[0, 1]$ , then you can perform the second type operation on first and second elements, so $a$ turns to $[1]$ .

In the fourth test case, it's obvious to see that you can't make any $1$ , no matter what you do.

In the fifth test case, you can first perform a type 2 operation on the first three elements so that $a$ becomes $[1, 0, 0, 1]$ , then perform a type 2 operation on the elements in positions two through four, so that $a$ becomes $[1, 1]$ , and finally perform the first type operation on the remaining elements, so that $a$ becomes $[1]$ .