AtCoder Alloy

AtCoder

IDcaddi2018b_b

Time2000ms

Memory256MB

Difficulty—

There are $N$ rectangular plate materials made of special metal called AtCoder Alloy. The dimensions of the $i$\-th material are $A_i \times B_i$ ($A_i$ vertically and $B_i$ horizontally). Takahashi wants a rectangular plate made of AtCoder Alloy whose dimensions are exactly $H \times W$. He is trying to obtain such a plate by choosing one of the $N$ materials and cutting it if necessary. When cutting a material, the cuts must be parallel to one of the sides of the material. Also, the materials have fixed directions and cannot be rotated. For example, a $5 \times 3$ material cannot be used as a $3 \times 5$ plate. Out of the $N$ materials, how many can produce an $H \times W$ plate if properly cut? ## Constraints * $1 \leq N \leq 1000$ * $1 \leq H \leq 10^9$ * $1 \leq W \leq 10^9$ * $1 \leq A_i \leq 10^9$ * $1 \leq B_i \leq 10^9$ ## Input Input is given from Standard Input in the following format: $N$ $H$ $W$ $A_1$ $B_1$ $A_2$ $B_2$ $:$ $A_N$ $B_N$ [samples]

Samples

Input #1

Output #1

2

Takahashi wants a $5 \times 2$ plate.

*   The dimensions of the first material are $10 \times 3$. We can obtain a $5 \times 2$ plate by properly cutting it.
*   The dimensions of the second material are $5 \times 2$. We can obtain a $5 \times 2$ plate without cutting it.
*   The dimensions of the third material are $2 \times 5$. We cannot obtain a $5 \times 2$ plate, whatever cuts are made. Note that the material cannot be rotated and used as a $5 \times 2$ plate.

Input #2

10 587586158 185430194
894597290 708587790
680395892 306946994
590262034 785368612
922328576 106880540
847058850 326169610
936315062 193149191
702035777 223363392
11672949 146832978
779291680 334178158
615808191 701464268

Output #2

API Response (JSON)

{
  "problem": {
    "name": "AtCoder Alloy",
    "description": {
      "content": "There are $N$ rectangular plate materials made of special metal called AtCoder Alloy. The dimensions of the $i$\\-th material are $A_i \\times B_i$ ($A_i$ vertically and $B_i$ horizontally). Takahashi w",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "caddi2018b_b"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "There are $N$ rectangular plate materials made of special metal called AtCoder Alloy. The dimensions of the $i$\\-th material are $A_i \\times B_i$ ($A_i$ vertically and $B_i$ horizontally).\nTakahashi w...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments