Jumping Takahashi

AtCoder

IDabc240_c

Time2000ms

Memory256MB

Difficulty—

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? ## 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. ## Input Input is given from Standard Input in the following format: $N$ $X$ $a_1$ $b_1$ $\vdots$ $a_N$ $b_N$ [samples]

Samples

Input #1

2 10
3 6
4 5

Output #1

Yes

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

Input #2

2 10
10 100
10 100

Output #2

No

He can be at the coordinate $X (= 10)$ after the first jump, but not after all jumps.

Input #3

Output #3

Yes

API Response (JSON)

{
  "problem": {
    "name": "Jumping Takahashi",
    "description": {
      "content": "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 ",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc240_c"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Takahashi is standing at the coordinate $0$ on a number line.\nHe 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.\nIs it possible ...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments