Problem:


Score: 400 points

Problem Statement

The Kingdom of Takahashi has N towns, numbered 1 through N.

There is one teleporter in each town. The teleporter in Town i (1 \leq i \leq N) sends you to Town A_i.

Takahashi, the king, loves the positive integer K. The selfish king wonders what town he will be in if he starts at Town 1 and uses a teleporter exactly K times from there.

Help the king by writing a program that answers this question.

Constraints

2 \leq N \leq 2 \times 10^5

1 \leq A_i \leq N

1 \leq K \leq 10^{18}

Input

Input is given from Standard Input in the following format:

N K
A_1 A_2 \dots A_N

Output

Print the integer representing the town the king will be in if he starts at Town 1 and uses a teleporter exactly K times from there.

Sample Input 1

4 5
3 2 4 1

Sample Output 1

4

If we start at Town 1 and use the teleporter 5 times, our travel will be as follows: 1 \to 3 \to 4 \to 1 \to 3 \to 4.

Sample Input 2

6 727202214173249351
6 5 2 5 3 2

Sample Output 2

2



Sample input:
4 5
3 2 4 1


Sample output:
4

Submission status: Wrong Answer

Solution code:
def main(sample_file = ''):

    """ convenient functions
    # for i, a in enumerate(iterable)
    # q, mod = divmod(a, b)
    # divmod(x, y) returns the tuple (x//y, x%y)
    # Higher-order function: reduce(operator.mul, xyz_count, 1)
    # manage median(s) using two heapq https://atcoder.jp/contests/abc127/tasks/abc127_f
    """

    """convenient decorator
    # @functools.lru_cache():
    # to facilitate use of recursive function
        # ex:
        # from functools import lru_cache
        # import sys
        # sys.setrecursionlimit(10**9)
        # @lru_cache(maxsize=None)
        # def fib(n):
        #     if n < 2:
        #         return n
        #     return fib(n-1) + fib(n-2)
        # print(fib(1000))
    """
    
    # import numpy as np
    import sys
    sys.setrecursionlimit(10**7)
    from itertools import accumulate, combinations, permutations, product # https://docs.python.org/ja/3/library/itertools.html
    # accumulate() returns iterator! to get list: list(accumulate())
    from math import factorial, ceil, floor, sqrt
    def factorize(n):
        """return the factors of the Arg and count of each factor
        
        Args:
            n (long): number to be resolved into factors
        
        Returns:
            list of tuples: factorize(220) returns [(2, 2), (5, 1), (11, 1)]
        """
        fct = []  # prime factor
        b, e = 2, 0  # base, exponent
        while b * b <= n:
            while n % b == 0:
                n = n // b
                e = e + 1
            if e > 0:
                fct.append((b, e))
            b, e = b + 1, 0
        if n > 1:
            fct.append((n, 1))
        return fct
    def combinations_count(n, r):   
        """Return the number of selecting r pieces of items from n kinds of items.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        # TODO: How should I do when n - r is negative?
        if n < 0 or r < 0:
            raise Exception('combinations_count(n, r) not defined when n or r is negative')
        if n - r < r: r = n - r
        if r < 0: return 0
        if r == 0: return 1
        if r == 1: return n
        numerator = [n - r + k + 1 for k in range(r)]
        denominator = [k + 1 for k in range(r)]
        for p in range(2,r+1):
            pivot = denominator[p - 1]
            if pivot > 1:
                offset = (n - r) % p
                for k in range(p-1,r,p):
                    numerator[k - offset] /= pivot
                    denominator[k] /= pivot
        result = 1
        for k in range(r):
            if numerator[k] > 1:
                result *= int(numerator[k])
        return result
    def combinations_with_replacement_count(n, r):
        """Return the number of selecting r pieces of items from n kinds of items allowing individual elements to be repeated more than once.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        if n < 0 or r < 0:
            raise Exception('combinations_with_replacement_count(n, r) not defined when n or r is negative')
        elif n == 0:
            return 1
        else:
            return combinations_count(n + r - 1, r)
    from bisect import bisect_left, bisect_right
    from collections import deque, Counter, defaultdict # https://docs.python.org/ja/3/library/collections.html#collections.deque
    from heapq import heapify, heappop, heappush, heappushpop, heapreplace,nlargest,nsmallest # https://docs.python.org/ja/3/library/heapq.html
    from copy import deepcopy, copy # https://docs.python.org/ja/3/library/copy.html
    import operator
    from operator import itemgetter #sort 
    # ex1: List.sort(key=itemgetter(1))
    # ex2: sorted(tuples, key=itemgetter(1,2))
    from functools import reduce, lru_cache
    def chmin(x, y):
        """change minimum
        if x > y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current minimum value
            y (long): potential minimum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x > y:
            x = y
            return (x, True)
        else:
            return (x, False)
    def chmax(x, y):
        """change maximum
        if x < y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current maximum value
            y (long): potential maximum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x < y:
            x = y
            return (x, True)
        else:
            return (x, False)

    from fractions import gcd # Deprecated since version 3.5: Use math.gcd() instead.
    def gcds(numbers):
        return reduce(gcd, numbers)
    def lcm(x, y):
        return (x * y) // gcd(x, y)
    def lcms(numbers):
        return reduce(lcm, numbers, 1)
    def make_divisors(n, reversed=False):
        """create list of divisors
        
        Args:
            number (int): number from which list of divisors is created
            reversed (bool, optional): ascending order if False. Defaults to False.
        
        Returns:
            list: list of divisors
        """
        divisors = set()
        for i in range(1, int(n**0.5)+1):
            if n % i == 0:
                divisors.add(i)
                divisors.add(n//i)
        return sorted(list(divisors),reverse=reversed)
    
    # first create factorial_list
    # fac_list = mod_factorial_list(n)
    INF = 10 ** 18
    MOD = 10 ** 9 + 7
    AtoZ = list('abcdefghijklmnopqrsruvwxyz') # 26
    modpow = lambda a, n, p = MOD: pow(a, n, p) # Recursive function in python is slow!
    def modinv(a, p = MOD):
        # evaluate reciprocal using Fermat's little theorem:
        # a**(p-1) is identical to 1 (mod p) when a and p is coprime
        return modpow(a, p-2, p)
    def modinv_list(n, p = MOD):
        if n <= 1:
            return [0,1][:n+1]
        else:
            inv_t = [0,1]
            for i in range(2, n+1):
                inv_t += [inv_t[p % i] * (p - int(p / i)) % p]
            return inv_t
    def modfactorial_list(n, p = MOD):
        if n == 0:
            return [1]
        else:
            l = [0] * (n+1)
            tmp = 1
            for i in range(1, n+1):
                tmp = tmp * i % p
                l[i] = tmp
            return l
    def modcomb(n, k, fac_list = [], p = MOD):
        # fac_list = modfactorial_list(100)
        # print(modcomb(100, 5, modfactorial_list(100)))
        from math import factorial
        if n < 0 or k < 0 or n < k: return 0
        if n == 0 or k == 0: return 1
        if len(fac_list) <= n:
            a = factorial(n) % p
            b = factorial(k) % p
            c = factorial(n-k) % p
        else:
            a = fac_list[n]
            b = fac_list[k]
            c = fac_list[n-k]
        return (a * modpow(b, p-2, p) * modpow(c, p-2, p)) % p
    def modadd(a, b, p = MOD):
        return (a + b) % MOD
    def modsub(a, b, p = MOD):
        return (a - b) % p
    def modmul(a, b, p = MOD):
        return ((a % p) * (b % p)) % p
    def moddiv(a, b, p = MOD):
        return modmul(a, modpow(b, p-2, p))

    class UnionFindTree:
        """union find tree class
        TODO: fix this description...
        how to use (example):
        >>  uf = UnionFindTree(N) 
        >>  if uf.find_root(a) == uf.find_root(b):
        >>      do something
        >>  else:
        >>      do something
        >>      uf.unite(a, b)
        """
        def __init__(self, N):
            self.root = [-1] * (N+1)
            self.rank   = [0]  * (N+1)
            self.connected_num = [1] * (N+1)
    
        def find_root(self,x):
            root = self.root
            while root[x] != -1:
                x = root[x]
            return x
    
        def unite(self,x,y):
            root = self.root
            rank = self.rank
            connected_num = self.connected_num
            find_root = self.find_root
    
            rx = find_root(x)
            ry = find_root(y)
            if rx != ry:
                if rank[rx] < rank[ry]:
                    root[rx] = ry
                    rx,ry = ry,rx
                else:
                    if rank[rx] == rank[ry]:
                        rank[rx] += 1
                    root[ry] = rx       
                connected_num[rx] += connected_num[ry]

    class SegTree:
        """
        ref: https://qiita.com/takayg1/items/c811bd07c21923d7ec69
        init(init_val, ide_ele): 配列init_valで初期化 O(N)
        update(k, x): k番目の値をxに更新 O(logN)
        query(l, r): 区間[l, r)をsegfuncしたものを返す O(logN)
        """
        def __init__(self, init_val, segfunc, ide_ele):
            """
            init_val: 配列の初期値
            segfunc: 区間にしたい操作
            ide_ele: 単位元
            n: 要素数
            num: n以上の最小の2のべき乗
            tree: セグメント木(1-index)
            """
            n = len(init_val)
            self.segfunc = segfunc
            self.ide_ele = ide_ele
            self.num = 1 << (n - 1).bit_length()
            self.tree = [ide_ele] * 2 * self.num
            # 配列の値を葉にセット
            for i in range(n):
                self.tree[self.num + i] = init_val[i]
            # 構築していく
            for i in range(self.num - 1, 0, -1):
                self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1])

        def update(self, k, x):
            """
            k番目の値をxに更新
            k: index(0-index)
            x: update value
            """
            k += self.num
            self.tree[k] = x
            while k > 1:
                self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1])
                k >>= 1

        def query(self, l, r):
            """
            [l, r)のsegfuncしたものを得る
            l: index(0-index)
            r: index(0-index)
            """
            res = self.ide_ele
            l += self.num
            r += self.num
            while l < r:
                if l & 1:
                    res = self.segfunc(res, self.tree[l])
                    l += 1
                if r & 1:
                    res = self.segfunc(res, self.tree[r - 1])
                l >>= 1
                r >>= 1
            return res

    # ************ Graph ************
    # Graph: https://en.wikipedia.org/wiki/Directed_graph
    # 最短経路問題: https://ja.wikipedia.org/wiki/%E6%9C%80%E7%9F%AD%E7%B5%8C%E8%B7%AF%E5%95%8F%E9%A1%8C
    
    # Bellman-Ford: O(|V||E|). Use this if there exists an edge with negative length in the graph
    # After N steps, the shortest path has converded if there doesn't exist an cycle of edges with negative
    # Watch out: d[N] == d[2*N] doesn't necessarily mean the graph doesn't have negative cycle
    # ref: https://www.youtube.com/watch?v=1Z6ofKN03_Y

    def BellmanFord(N, M, ABC, vertex_start, vertex_end, value_if_inf = -1, find_shortest = False):
        """to calculate furthest or shortest length between vertex_start and vertex_end using BellmanFord algorithm
        
        Args:
            N (int): number of vertices
            M (int): number of edges
            ABC (list): [(ai, bi, ci) for _ in range(N)] where i-th edge is directed from vertex ai to vertex bi and the length is ci 
            vertex_start (int): start vertex. usually use 0.
            vertex_end (int): end vertex. usually use N-1.
            value_if_inf (int or string as you like, optional): value you want when the furthest (or shortest) distance is infinite (or -infinite). Defaults to -1.
            find_shortest (bool, optional): choose False to find furthest path. Defaults to False.
        
        Returns:
            int or string: normally int (but can be str if you set value_if_inf to str)
            
        Example:
                N, M, P = R()
                ABC = [R() for _ in range(M)]
                ABC = [(a-1, b-1, c-P) for a, b, c in ABC]
                print(BellmanFord(N, M, ABC, 0, N-1, value_if_inf = 'inf'))

        """

        def make_reachable_list(N, M, ABC, vertex_start, vertex_end):
            reachable_to_direct = defaultdict(list)
            reachable_from_direct = defaultdict(list)
            reachable_from_start = [False] * N
            reachable_to_end = [False] * N
            reachable_from_start[vertex_start] = True
            reachable_to_end[vertex_end] = True
            reachable_from_both_sides = [False] * N
            dfs_from_start = []
            dfs_to_end = []
            for a, b, c in ABC:
                reachable_to_direct[a].append(b)
                reachable_from_direct[b].append(a)
                if a == vertex_start:
                    dfs_from_start.append(b)
                    reachable_from_start[b] = True
                if b == vertex_end:
                    dfs_to_end.append(a)
                    reachable_to_end[a] = True
            while dfs_from_start:
                v = dfs_from_start.pop()
                for i in reachable_to_direct[v]:
                    if not reachable_from_start[i]:
                        reachable_from_start[i] = True
                        dfs_from_start.append(i)
            while dfs_to_end:
                v = dfs_to_end.pop()
                for i in reachable_from_direct[v]:
                    if not reachable_to_end[i]:
                        reachable_to_end[i] = True
                        dfs_to_end.append(i)
            for i in range(N):
                reachable_from_both_sides[i] = reachable_from_start[i] and reachable_to_end[i]
            return reachable_from_both_sides
        
        reachable_from_both_sides = make_reachable_list(N, M, ABC, vertex_start, vertex_end)
        
        if find_shortest:
            dist = [INF for i in range(N)]
        else:
            dist = [-INF for i in range(N)]
        
        dist[vertex_start] = 0
        for i in range(N):
            updated = False
            for a, b, c in ABC:
                if not reachable_from_both_sides[a]:
                    continue
                elif find_shortest:
                    update_condition = dist[a] + c < dist[b]
                else:
                    update_condition = dist[a] + c > dist[b]
                if dist[a] != INF and update_condition:
                    dist[b] = dist[a] + c
                    updated = True
                    if i == N-1:
                        return value_if_inf
            if not updated:
                break
        return dist[vertex_end]

    # Warshall Floyd O(V**3)
    def warshall_floyd(number_vertex, XYD, shift_one_for_vertex=False):
        # ref: https://juppy.hatenablog.com/entry/2018/11/01/%E8%9F%BB%E6%9C%AC_python_%E5%85%A8%E7%82%B9%E5%AF%BE%E6%9C%80%E7%9F%AD%E7%B5%8C%E8%B7%AF%E6%B3%95%EF%BC%88%E3%83%AF%E3%83%BC%E3%82%B7%E3%83%A3%E3%83%AB%E3%83%95%E3%83%AD%E3%82%A4%E3%83%89%E6%B3%95
        # number_vertex: len(vertex)
        # XYD: list of distance from x to y
        # shift_one_for_vertex: XYDの値が1~Nの時(0~N-1でない時)に調整するフラグ。
        # d[i][j]: iからjへの最短距離
        d = [[float("inf")]*number_vertex for i in range(number_vertex)]
        for x, y, dist in XYD:
            if shift_one_for_vertex:
                x = x - 1
                y = y - 1
            d[x][y] = dist
            d[y][x] = dist
        for i in range(number_vertex):
            d[i][i] = 0 # distance of same vertex is 0
        for k in range(number_vertex):
            for i in range(number_vertex):
                for j in range(number_vertex):
                    d[i][j] = min(d[i][j],d[i][k] + d[k][j])
        return d


    """ initialize variables and set inputs
    # initialize variables
        # to initialize list, use [0] * n
        # to initialize two dimentional array:
            # ex) [[0] * N for _ in range(N)]
            # ex2) dp = [[0] * (N+1) for _ in range(W*2)]
    # set inputs
        # put inputs between specific values (almost as quickly)
        # ex) S = [-INF] + [int(r()) for _ in range(A)] + [INF]
        # open(0).read() is sometimes useful:
        # ex) n, m, *x = map(int, open(0).read().split())
        #     min(x[::2]) - max(x[1::2])
        # ex2) *x, = map(int, open(0).read().split())
        #     don't forget to add comma after *x if only one variable is used
    # preprocessing
        # transpose = [x for x in zip(*data)]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [(1, 4, 7), (2, 5, 8), (3, 6, 9)]
        # flat = [flatten for inner in data for flatten in inner]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [1, 2, 3, 4, 5, 6, 7, 8, 9]
    # calculate and output
        # output pattern
        # ex1) print(*l) => when l = [2, 5, 6], printed 2 5 6
    """

    # functions to read input
    r = lambda: sys.stdin.readline().strip()
    r_int = lambda: int(r())
    r_float = lambda: float(r())
    R = lambda: list(map(int, r().split()))
    R_str = lambda: r().split()
    R_map = lambda: map(int, r().split())
    R_float = lambda: list(map(float, r().split()))
    R_tuple = lambda: tuple(map(int, r().split()))

    """ how to treat input
    # single int: int(r())
    # single string: r()
    # single float: float(r())
    # line int: R()
    # line string: r().split()
    # line (str, int, int): [j if i == 0 else int(j) for i, j in enumerate(r().split())]
    # lines int: [R() for _ in range(n)]
    """

    # for test
    if sample_file:
        sys.stdin = open(sample_file)
        
    # ----------------------------------
    # main
    #%%
    N, K = R()
    A = R()
    arrived = [False] * N
    here = 0
    arrived[0] = True
    first_visit = [-1] * N
    visiting = 0
    first_visit[0] = visiting
    while True:
        here = A[here] - 1
        visiting += 1
        if arrived[here]:
            loop_num = visiting - first_visit[here]
            break
        else:
            arrived[here] = True
            first_visit[here] = visiting
    kk = K - first_visit[here] 
    if kk < 0:
        here = 0
        for i in range(K):
            here = A[here]
        print(here+1)
        return
    kkk = kk % loop_num
    for i in range(kkk):
        here = A[here] - 1
    print(here+1)
    
            
        
        
        

        
    
    
    # 小文字をカウントしたリストを持つセグ木で行けそう。

    
    # a = [14, 5, 9, 13, 7, 12, 11, 1, 7, 8]
    


    #%%
    # end of main
    # ----------------------------------

    """memo: how to use defaultdict of list
    # initialize
    Dic = defaultdict(list)
    # append / extend
    Dic[x].append(y)
    # three methods for loop: keys(), values(), items()
    for k, v in Dic.items():
    """
    
    """memo: how to solve binary problems
    # to make binary digits text
    >>> a = 5
    >>> bin_str_a = format(a, '#06b')
    >>> print(bin_str_a)
    0b0101 # first 2 strings (='0b') indicates it is binary
    """
    
    """memo: how to solve the problem
    creating simple test/answer
    greed
    simple dp
    graph
    """

if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
s = list(map(int,input().split()))
n=s[0]
k=s[1]
s = list(map(int, input().split()))
ans=1
path=[1]
for i in range(k):
    ans=s[ans-1]
    if ans in path:
        loop = path[path.index(ans):]
        ran=len(loop)
        ansour=(k-i-1)%ran
        print(loop[ansour])
        break
    path.append(ans)

Submission status: Wrong Answer

Solution code:
n, k = map(int, input().split())
a = list(map(int, input().split()))
s = []
ans = a[0]
t = 0 
for i in range(k):
    t = a[ans-1]
    ans = a[t-1]
    if ans in s:
        break
    s.append(ans)
if len(s) < 2:
    print(s[0])
else:
    r = k % len(s)
    print(s[r-1])

Submission status: Wrong Answer

Solution code:
def detectCycle(x, a):
    start,length = 0, 1
    p1, p2 = a[x], a[a[x]]
    while p1 != p2:
        p1, p2 = a[p1], a[a[p2]]

    p2 = x
    while p1 != p2:
        p1, p2 = a[p1], a[p2]
        start += 1

    p2 = a[p1]
    while p1 != p2:
        p2 = a[p2]
        length += 1
    
    return (start,length)

n, k = (int(x) for x in input().split())
a = [int(x)-1 for x in input().split()]
info = detectCycle(0,a)

loc = 0
k -= info[0]
for i in range(info[0]):
    loc = a[loc]

k %= info[1]
for i in range(k):
    loc = a[loc]
print(loc+1)

Submission status: Wrong Answer

Solution code:
import numpy as np

N, K = map(int, input().split())

A = np.array(list(map(int, input().split()))) - 1

roop = [-1]*N
is_visited = [-1]*N

roop[0] = 0
is_visited[0] = 0

for i in range(N-1):
    if is_visited[A[roop[i]]] >= 0:
        for idx, j in enumerate(roop):
            if j == A[roop[i]]:
                r = i+1-idx
                print(roop[idx + (K - idx) % r] + 1)
                exit()

    roop[i+1] =  A[roop[i]]
    is_visited[roop[i]] = i


    if i == K:
        print(roop[i])
        exit()

Submission status: Wrong Answer

Solution code:
def main():
    n,k=map(int,input().split())
    a=list(map(int,input().split()))
    cnt=0
    b=[1]
    res=[-1]*n
    res[0]=0
    flg=0
    now=1
    start=0
    t=1
    while flg==0:
        cnt+=1
        if res[a[now-1]-1]==-1:
            res[a[now-1]-1]=cnt
            b.append(a[now-1])
            now=a[now-1]
            print(now)
        else:
            start=res[a[now-1]-1]
            t=cnt-start
            if cnt<=k:
                flg=1
                k-=start
            else:
                flg=2
            print(cnt,a[now-1],res,flg)
    print(start,t)
    print(b)
    if flg==1:
        print(b[start+(k%t)])
    else:
        print(b[k])
if __name__=="__main__":
    main()

Submission status: Wrong Answer

Solution code:
n,k=map(int,input().split())
a=[0]
a.extend(list(map(int,input().split())))
loop=[]
now=0
for  i in range(1,n+1):
    if i==1:
        now=a[1]
        loop.append(now)
    else:
        now=a[now]
        if now!=a[1]:
            loop.append(now)
        else:
            break

count=k%len(loop)
if count ==0:
    print(loop[-1])
else:
    print(loop[count-1])

Submission status: Wrong Answer

Solution code:
# from math import factorial,sqrt,ceil,gcd
# from itertools import permutations,combinations,combinations_with_replacement
# from collections import deque,Counter
# import re
# from functools import lru_cache # 簡単メモ化 @lru_cache(maxsize=1000)
# from decimal import Decimal, getcontext
# # getcontext().prec = 1000
# # eps = Decimal(10) ** (-100)

# import numpy as np
# import networkx as nx
# from scipy.sparse.csgraph import shortest_path, dijkstra, floyd_warshall, bellman_ford, johnson
# from scipy.sparse import csr_matrix
# from scipy.special import comb

# slist = "abcdefghijklmnopqrstuvwxyz"
N,K = map(int,input().split())
lisA = [0] + list(map(int,input().split()))
# arrA = np.array(input().split(),dtype=np.int64)

checked = [1]
i = 1
while not lisA[i] in checked:
    checked.append(lisA[i])
    i = lisA[i]
else:
    checked.append(lisA[i])

# print(checked)
idx = checked.index(checked[-1])
warukazu = len(checked[idx:-1])
ans = checked[idx:][(K-idx) % warukazu]
print(ans)
# print(*ans)   # unpackして出力。間にスペースが入る
# for row in board:
#     print(*row,sep="")    #unpackして間にスペース入れずに出力する
# print("{:.10f}".format(ans))
# print("{:0=10d}".format(ans))

Submission status: Wrong Answer

Solution code:
n,k=list(map(int,input().split()))
A=list(map(int,input().split()))
start,i=1,0
root=[1]

while True:
  start=A[start-1]
  if start in root:
    i = start
    break
  root.append(start)
  
if k <= len(root):
  print(root[k-1])
else:
  s=root.index(i)
  newroot=root[s:]
  ans=(k-len(root))%len(newroot)
  print(newroot[ans])

Submission status: Wrong Answer

Solution code:
N, K = map(int, input().split())
A = list(map(int, input().split()))
Kn = [0]*N
l = [1]
p = 0
i = 1
while True:
    Kn[p] = 1
    # print(p)
    if Kn[A[p]-1] == 1:
        #print(l)
        sp = l.index(A[p])
        ep = len(l)-1
        break
    elif i == K:
        print(p+1)
    l.append(A[p])
    p = A[p]-1
    i += 1
l = l[sp:]
K+=1
K-=sp
#print(sp, ep, l, K)
if K % len(l) == 0:
    print(l[len(l)-1])
else:
    print(l[K % (len(l)-1)])

Submission status: Wrong Answer

Solution code:
#!/usr/bin/env python3


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    # Failed to predict input format
    N, K = list(map(int, input().split()))
    A = [x-1 for x in list(map(int, input().split()))]

    len_cycle = 0
    start = 0
    already_visit = set([0])
    loop_node = -1
    while True:
        start = A[start]
        len_cycle += 1
        if start in already_visit or len_cycle > N:
            loop_node = start
            break
        else:
            already_visit.add(start)

    if loop_node != 0:
        dist_loop_node = 0
        start = 0
        while True:
            start = A[start]
            dist_loop_node += 1
            if start == loop_node:
                break
        len_cycle -= dist_loop_node

    len_move = K % len_cycle
    start = 0
    for _ in range(len_move):
        start = A[start]
    print(start+1)
    pass

if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
n, x = (int(x) for x in input().split())
s = (int(x) for x in input().split())
a = []
for c in s:
    a.append(int(c))

que = []
que.append(1)
while True:
    if a[que[-1] - 1] not in que:
        que.append(a[que[-1] - 1])
    else:
        start = que.index(a[que[-1] - 1])
        break

x -= start
x = x % (len(que) - start)
que = que[start:]
print(que[x])

Submission status: Wrong Answer

Solution code:
n, k = map(int, input().split())

an = list(map(int, input().split()))

tp = []
current = 1
tp.append(1)
if k > n:
  for i in range(n):
    current = an[current-1]
    tp.append(current)
  tps = len(set(tp))
  tp = tp[0:tps]
    
  kurikaesi_start = an[tp[-1]-1]
  start_ind = tp.index(kurikaesi_start)
  num = (k - start_ind) % (tps - start_ind)
  
  print(tp[start_ind+num])
else:
  for i in range(k):
    current = an[current]
  print(current)

Submission status: Wrong Answer

Solution code:
import sys
sys.setrecursionlimit(10**6)
from math import floor,ceil,sqrt,factorial,log
from heapq import heappop, heappush, heappushpop
from collections import Counter,defaultdict,deque
from itertools import accumulate,permutations,combinations,product,combinations_with_replacement
from bisect import bisect_left,bisect_right
from copy import deepcopy
from operator import itemgetter
from fractions import gcd
mod = 10 ** 9 + 7
inf = float('inf')
ninf = -float('inf')
 
#整数input
def ii(): return int(sys.stdin.readline().rstrip()) #int(input())
def mii(): return map(int,sys.stdin.readline().rstrip().split())
def limii(): return list(mii()) #list(map(int,input().split()))
def lin(n:int): return [ii() for _ in range(n)]
def llint(n: int): return [limii() for _ in range(n)]
#文字列input
def ss(): return sys.stdin.readline().rstrip() #input()
def mss(): return sys.stdin.readline().rstrip().split()
def limss(): return list(mss()) #list(input().split())
def lst(n:int): return [ss() for _ in range(n)]
def llstr(n: int): return [limss() for _ in range(n)]

#本当に貪欲法か？ DP法では？？
#本当に貪欲法か？ DP法では？？
#本当に貪欲法か？ DP法では？？
n,k=mii()
arr=limii()

visited=[0]*n

i=0

town=[0]

while visited[i]==0:
    visited[i]=1
    if i==0:
        visited[i]=1
    
    i=arr[i]-1

    town.append(i)

#town=[0, 5, 1, 4, 2, 1]
b=town.index(town[-1])
#at=[1, 4, 2]
at=deepcopy(town[b:-1])
#print(at,b)
if k<=b:
    print(town[k])
    exit()

else:
    k-=b
    #print(k)
    a=k%len(at)
    #print(a)
    #print(at)
    print(at[a]+1)

Submission status: Wrong Answer

Solution code:
N,K=map(int,input().split())
A=list(map(int,input().split()))
index=[0]
index.append(A[0]-1)
flag=0
count=0
for _ in range(K):
    #print(index)
    t=index[-1]
    if (A[t]-1) in index:
        index.append(A[t]-1)
        flag=1
        break
    index.append(A[t]-1)
if flag==0:
    print(index[-1]+1)
    exit()
check = index[-1]
for i,c in enumerate(index):
    if c==check:
        a_path=i
        break
K-=a_path
t=len(index)-1-a_path
print(index[a_path+K%t]+1)
#print(index)

Submission status: Wrong Answer

Solution code:
import sys
readline = sys.stdin.buffer.readline


N, K = map(int, readline().split())
A = list(map(int, readline().split()))

P = []
c = 0
for _ in range(N):
    c = A[c] - 1
    P.append(c)
    if c == 0:
        break

n = len(P)
m = K % n

print(P[m-1] + 1)

Submission status: Wrong Answer

Solution code:
n, k = map(int, input().split())
a = list(map(int, input().split()))

print(n, k)
print(a)
now = 1
k = k % n

for i in range(k):
    now = a[now-1]

print(now)

Submission status: Wrong Answer

Solution code:
N,K = map(int,input().split())
list1 = list(map(int,input().split()))
visited_town = [[] for i in range(N+1)] #どの町にいつ訪れたか,配列の0あける。
visited_time = [None for i in range(2*N)] #訪れた町の時系列。こっちは0あけない。

visited_town[1].append(0) 
visited_time[0] = 1

cycle_start = -1
cycle_end = -1

for i in range(1,2*N):
  next_city = list1[visited_time[i-1]-1]
  visited_town[next_city].append(i)
  visited_time[i] = next_city
  if len(visited_town[next_city]) == 2:
    cycle_start = visited_town[next_city][0]
    cycle_end = visited_town[next_city][1]
    break

if cycle_start == -1:
  ans = visited_time[K]
  print(ans)
else :   
  syuuki = cycle_end-cycle_start
  cycle = visited_time[cycle_start:cycle_end]
  ans = cycle[(K-cycle_start) % syuuki]
  print(ans)

Submission status: Wrong Answer

Solution code:
n, k = map(int, input().split())
A = list(map(int, input().split()))
posi = 1
tran = [1]
for i in range(10):
    posi = A[posi-1]
    if posi in tran:
        break
    tran.append(posi)
roop = tran[tran.index(posi):]
div = len(tran) - len(roop)
k -= div
p = len(roop)
q = k%p
print(roop[q])

Submission status: Wrong Answer

Solution code:
import sys
def S(): return sys.stdin.readline().rstrip()
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LS(): return list(sys.stdin.readline().rstrip().split())

n,k = MI()
a = LI()

b = [0]
visited = [0]*n
for _ in range(n):
    if visited[a[b[-1]]-1] == 1:
        break
    visited[a[b[-1]]-1] = 1
    b.append(a[b[-1]]-1)
first = b.index(a[b[-1]]-1)
second = len(b)
print(b[(k-first)%(second-first)+first]+1)