CF1795B.Ideal Point

传统题 时间 2000 ms 内存 256 MiB 4 尝试 1 已通过 1 标签

Ideal Point

You are given nn one-dimensional segments (each segment is denoted by two integers — its endpoints).

Let's define the function f(x)f(x) as the number of segments covering point xx (a segment covers the point xx if lxrl \le x \le r, where ll is the left endpoint and rr is the right endpoint of the segment).

An integer point xx is called ideal if it belongs to more segments than any other integer point, i. e. f(y)<f(x)f(y) \lt f(x) is true for any other integer point yy.

You are given an integer kk. Your task is to determine whether it is possible to remove some (possibly zero) segments, so that the given point kk becomes ideal.

Input

The first line contains one integer tt (1t10001 \le t \le 1000) — the number of test cases.

The first line of each test case contains two integers nn and kk (1n,k501 \le n, k \le 50).

Then nn lines follow, ii-th line of them contains two integers lil_i and rir_i (1li,ri501 \le l_i, r_i \le 50; liril_i \le r_i) — the endpoints of the ii-th segment.

Output

For each test case, print YES if it is possible to remove some (possibly zero) segments, so that the given point kk becomes ideal, otherwise print NO.

You may print each letter in any case (YES, yes, Yes will all be recognized as positive answer, NO, no and nO will all be recognized as negative answer).

Note

In the first example, the point 33 is already ideal (it is covered by three segments), so you don't have to delete anything.

In the fourth example, you can delete everything except the segment [5,5][5, 5].

Samples

4
4 3
1 3
7 9
2 5
3 6
2 9
1 4
3 7
1 3
2 4
3 5
1 4
6 7
5 5
YES
NO
NO
YES

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