Problem9555--ABC240 —— C - Jumping Takahashi

9555: ABC240 —— C - Jumping Takahashi

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

Takahashi is standing at the coordinate $0$ on a number line.

He will now perform $N$ jumps. In the $i$-th jump $(1 \leq i \leq N)$, he moves $a_i$ or $b_i$ in the positive direction.

Is it possible for him to be at the coordinate $X$ after $N$ jumps?

Input

Input is given from Standard Input in the following format:

```
$N$ $X$
$a_1$ $b_1$
$\vdots$
$a_N$ $b_N$
```

Output

If it is possible for Takahashi to be at the coordinate $X$ after $N$ jumps, print `Yes`; otherwise, print `No`.

Constraints

-   $1 \leq N \leq 100$
-   $1 \leq a_i \lt b_i \leq 100 \, (1 \leq i \leq N)$
-   $1 \leq X \leq 10000$
-   All values in input are integers.

Sample 1 Input

2 10
3 6
4 5

Sample 1 Output

Yes
By moving $b_1(=6)$ in the first jump and $a_2(=4)$ in the second jump, he can be at the coordinate X(=10).

Sample 2 Input

2 10
10 100
10 100

Sample 2 Output

No
He can be at the coordinate X(=10) after the first jump, but not after all jumps.

Sample 3 Input

4 12
1 8
5 7
3 4
2 6

Sample 3 Output

Yes

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