Piano 3

AtCoder

IDabc369_b

Time2000ms

Memory256MB

Difficulty—

Takahashi has a piano with $100$ keys arranged in a row. The $i$\-th key from the left is called key $i$. He will play music by pressing $N$ keys one by one. For the $i$\-th press, he will press key $A_i$, using his left hand if $S_i=$ `L`, and his right hand if $S_i=$ `R`. Before starting to play, he can place both of his hands on any keys he likes, and his **fatigue level** at this point is 0. During the performance, if he moves one hand from key $x$ to key $y$, the fatigue level increases by $|y-x|$ (conversely, the fatigue level does not increase for any reason other than moving hands). To press a certain key with a hand, that hand must be placed on that key. Find the minimum possible fatigue level at the end of the performance. ## Constraints * $1 \leq N \leq 100$ * $1 \leq A_i \leq 100$ * $N$ and $A_i$ are integers. * $S_i$ is `L` or `R`. ## Input The input is given from Standard Input in the following format: $N$ $A_1$ $S_1$ $A_2$ $S_2$ $\vdots$ $A_N$ $S_N$ [samples]

Samples

Input #1

4
3 L
6 R
9 L
1 R

Output #1

11

For example, the performance can be done as follows:

*   Initially, place the left hand on key $3$ and the right hand on key $6$.
*   Press key $3$ with the left hand.
*   Press key $6$ with the right hand.
*   Move the left hand from key $3$ to key $9$. The fatigue level increases by $|9-3| = 6$.
*   Move the right hand from key $6$ to key $1$. The fatigue level increases by $|1-6| = 5$.
*   Press key $9$ with the left hand.
*   Press key $1$ with the right hand.

In this case, the fatigue level at the end of the performance is $6+5 = 11$, which is the minimum possible.

Input #2

Output #2

Input #3

Output #3

API Response (JSON)

{
  "problem": {
    "name": "Piano 3",
    "description": {
      "content": "Takahashi has a piano with $100$ keys arranged in a row. The $i$\\-th key from the left is called key $i$. He will play music by pressing $N$ keys one by one. For the $i$\\-th press, he will press key $",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc369_b"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Takahashi has a piano with $100$ keys arranged in a row. The $i$\\-th key from the left is called key $i$.\nHe will play music by pressing $N$ keys one by one. For the $i$\\-th press, he will press key $...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments