Ancestor

AtCoder

IDabc263_b

Time2000ms

Memory256MB

Difficulty—

There are $N$ people, called Person $1$, Person $2$, $\ldots$, Person $N$. The parent of Person $i$ $(2 \le i \le N)$ is Person $P_i$. Here, it is guaranteed that $P_i < i$. How many generations away from Person $N$ is Person $1$? ## Constraints * $2 \le N \le 50$ * $1 \le P_i < i(2 \le i \le N)$ * All values in input are integers. ## Input Input is given from Standard Input in the following format: $N$ $P_2$ $P_3$ $\dots$ $P_N$ [samples]

Samples

Input #1

3
1 2

Output #1

2

Person $2$ is a parent of Person $3$, and thus is one generation away from Person $3$.
Person $1$ is a parent of Person $2$, and thus is two generations away from Person $3$.
Therefore, the answer is $2$.

Input #2

10
1 2 3 4 5 6 7 8 9

Output #2

API Response (JSON)

{
  "problem": {
    "name": "Ancestor",
    "description": {
      "content": "There are $N$ people, called Person $1$, Person $2$, $\\ldots$, Person $N$. The parent of Person $i$ $(2 \\le i \\le N)$ is Person $P_i$. Here, it is guaranteed that $P_i < i$. How many generations away ",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc263_b"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "There are $N$ people, called Person $1$, Person $2$, $\\ldots$, Person $N$.\nThe parent of Person $i$ $(2 \\le i \\le N)$ is Person $P_i$. Here, it is guaranteed that $P_i < i$.\nHow many generations away ...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments