Submission #538535

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Source Code Expand

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.IO;

class Myon
{

    public Myon() { }
    public static int Main()
    {
        new Myon().calc();
        return 0;
    }

    Scanner cin;

    void calc()
    {
        cin = new Scanner();
        int N = cin.nextInt();
        int a = cin.nextInt() - 1;
        string k = cin.next();
        int[] b = new int[N];
        for (int i = 0; i < N; i++)
        {
            b[i] = cin.nextInt() - 1;
        }

        int[] visited = new int[N];
        int step = 1;
        int pos = a;
        while (visited[pos] == 0)
        {
            visited[pos] = step;
            step++;
            pos = b[pos];
        }
        int loop = step - visited[pos];

        int now = 0;
        bool check = false;
        for (int i = 0; i < k.Length; i++)
        {
            now = now * 10 + (k[i] - '0');
            if (now > N)
            {
                now %= loop;
                check = true;
            }
        }

        //減らし過ぎた分を適当に足す
        if (check)
        {
            int add = 0;
            while (add < N) add += loop;

            now += add;
        }

        pos = a;
        for (int i = 0; i < now; i++)
        {
            pos = b[pos];
        }
        Console.WriteLine(pos + 1);
    }
}





class Scanner
{
    string[] s;
    int i;

    char[] cs = new char[] { ' ' };

    public Scanner()
    {
        s = new string[0];
        i = 0;
    }

    public string next()
    {
        if (i < s.Length) return s[i++];
        string st = Console.ReadLine();
        while (st == "") st = Console.ReadLine();
        s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
        i = 0;
        return next();
    }

    public int nextInt()
    {
        return int.Parse(next());
    }

    public long nextLong()
    {
        return long.Parse(next());
    }

    public double nextDouble()
    {
        return double.Parse(next());
    }

}

Submission Info

Judge Result