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:
# coding: utf-8
import sys
sysread = sys.stdin.readline
read = sys.stdin.read
sys.setrecursionlimit(10**7)
def run():
    N,K = map(int, sysread().split())
    A = [0] + list(map(int, sysread().split()))
    perm = [1]
    seen = [[-1, False] for _ in range(N+1)]
    seen[1] = [1,True]
    l = 1
    while True:
        v = perm[-1]
        idx, boo =  seen[A[v]]
        if boo: break
        l += 1
        perm.append(A[v])
        seen[A[v]] = [l,True]

    K -= idx - 1
    perm = perm[idx-1:]
    print(perm[K % len(perm)])



if __name__ == "__main__":
    run()

Submission status: Wrong Answer

Solution code:
from sys import stdin
input = stdin.readline

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

graph = []

time = [-1] * N

for i in range(N):
    graph.append([i, A[i]])

now = 0
nex = 0
time[0] = 0
loop = 0

while True:
    now = nex
    nex = A[now] - 1

    if time[nex] == -1:
        time[nex] = time[now] + 1
    else:
        loop = nex
        break

if K > max(time):
    K -= time[loop]
    K %= (max(time) - time[loop] + 1)
    for i in range(N):
        time[i] -= time[loop]

for i in range(N):
    if time[i] == K:
        print(i + 1)

# print(time, K)

Submission status: Wrong Answer

Solution code:
n,k=map(int,input().split())
a=list(map(int,input().split()))
d={}
cnt=[]
m=0
ans=0
for i in range(2*n):
  if a[m] in d:
    ans+=1
    cnt.append(a[m])
    if ans==k:
      print(a[m])
    break
  else:
    d[a[m]]=0
    cnt.append(a[m])
    ans+=1
    if ans==k:
      print(a[m])
      break
    m=a[m]-1
if ans!=k:
  if cnt[-1]==cnt[-2]:
    print(cnt[-1])
  else:
    cnt=cnt[cnt.index(cnt[-1]):-2]
    print(cnt[(k-ans)%len(cnt)])

Submission status: Wrong Answer

Solution code:
n,k=map(int,input().split(' '))
a=list(map(int,input().split(' ')))
loc=1
begin=0
end=0
d={}
for i in range(n):
    loc=a[loc-1]
    if loc in d.keys():
        begin=d[loc]
        end=i+1
        break
    d[loc]=i+1
if k<=end:
    end=0
if end !=0:
    k=(k-begin+1)%(end-begin)+begin-1
loc=1
for _ in range(k):
    loc=a[loc-1]
print(loc)

Submission status: Wrong Answer

Solution code:
n,k=map(int,input().split())
a=list(map(int,input().split()))
chk=[0]
x=-1
while chk:
    x=chk[-1]
    if a[x]-1 in chk:
        x=a[x]-1
        break
    else:
        chk.append(a[x]-1)
l1=0
while chk[l1]!=x:
    l1+=1
l2=len(chk)-l1
print(chk[l1+((k-l1)%l2)]+1)

Submission status: Wrong Answer

Solution code:
n,k = map(int,input().split())
a_ls = list(map(int, input().split()))
a_ls = [0] + a_ls

visited_ls = []
now = 1
times = 0
while True:
    visited_ls.append(now)
    times += 1
    nex = a_ls[now]
    if nex in visited_ls:
        first_ind = visited_ls.index(nex)
        before_loop = first_ind
        loop_ls = visited_ls[first_ind:times]
        break
    now = nex
ind = (k - before_loop) % len(loop_ls)
print(loop_ls[ind])

Submission status: Wrong Answer

Solution code:
N, K = map(int, input().split())
Al = list(map(int, input().split()))
Al = [0] + Al

l = [1]
i = 1
for _ in range(len(Al)-1):
    if Al[i] not in l:
        l.append(Al[i])
        i = Al[i]
    else:
        i = Al[i]
        break

if K<=(l.index(i)+1):
    print(l[K-1])
else:
    l_new = l[l.index(i):]
    print(l_new[(K-l.index(i))%len(l_new)])

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 = 1
    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] + 1
    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:
n, k = map(int, input().split())
an = list(map(int, input().split())) 

group = [0]
now = 0
seen = [0]*n
seen[0] = 1
while True:
    now = an[now] - 1
    
    group.append(now)
    if seen[now] == 1:
        break
    seen[now] = 1

l = len(group)
a = group.index(group[-1])
roop = l - a - 1
if k < a:
    print(group[k])
else:
    x = (k - a) % roop
    print(group[a + x] + 1)

Submission status: Wrong Answer

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


def solve(N, K, A):
    visited = [1]
    now = 1
    b = 0
    l = 0
    for _ in range(N):
        now = A[now - 1]
        if now in visited:
            b = visited.index(now)
            l = len(visited) - b
            break
        else:
            visited.append(now)
    x = (K - b) % l
    print(visited[b + x])
    return

# 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():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    K = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]
    solve(N, K, A)


if __name__ == '__main__':
    main()

Submission status: Wrong Answer

Solution code:
N, K = map(int, input().split())
A = [int(i) for i in input().split()]

first = {}
first[1] = 0
second = {}
flag = 1
i = 0
warp = 1
while flag:
    if A[i] in first.keys():
        second[A[i]] = warp
        flag = 0
        break
    first[A[i]] = warp
    i = A[i] - 1
    warp += 1

loop_town = []
stand = 0
for key, value in second.items():
    stand = first[key]
    loop = value - first[key]
    for key2, value2 in first.items():
        if first[key] <= value2 < value:
            loop_town.append(key2) 

print(loop_town[(K-stand)%loop])

Submission status: Wrong Answer

Solution code:
N, K = map(int, input().split())
A = list(map(int, input().split()))
tele = [0] * N
for i in range(N):
    tele[i] = A[i] - 1
now = 0
cnt = 0
exp = [False] * N
period = 0
loop = False
start = -1
while cnt < K:
    exp[now] = True
    now = tele[now]
    cnt += 1
    if loop:
        period += 1
        if now == start:
            loop = False
            cnt += K - ((K - cnt) % period)
    if exp[now] and (not loop):
        loop = True
        start = now
    # print(now, exp, cnt, period, start)
print(now+1)

Submission status: Wrong Answer

Solution code:
n,k = map(int,input().split())
a = [0]+list(map(int,input().split()))
visited = [0]*(n+1)
turn = [0]*(n+1)
visited[1] = 0
nxt = 1
i = 1
while True:
  if visited[a[nxt]]:
    nxt2 = a[nxt]
    break
  turn[a[nxt]] = i
  visited[nxt] = 1
  i += 1
  nxt = a[nxt]

loop = i-turn[nxt2]
if turn[nxt2] == 0:
  loop = i
  start = 0
start = turn[nxt2]
#print(turn,i)
#print(start,loop)
if k < i:
  print(turn.index(k))
else:
  print(turn.index(((k-start)%loop)+start))

Submission status: Wrong Answer

Solution code:
# -*- coding: utf-8 -*-
"""
Created on Sun May 10 20:50:56 2020
"""

import sys
#import numpy as np

sys.setrecursionlimit(10 ** 9)
#def input():
#    return sys.stdin.readline()[:-1]
mod = 10**9+7

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

city = [False for i in range(N)]
city[1-1] =True
now = 1

counta1 = 0
while True:
    counta1 += 1
    prev = now
    now = A[now-1]
#    print(prev,now,counta1)
    if city[now-1]:
        break
    else:
        city[now-1] = True

counta = 1
rout = []
rout.append(now)
while now != prev:
    now = A[now-1]
    rout.append(now)
    counta +=1
#    print(now,rout,counta)

ans = rout[(K-counta1) % counta]
print(ans)

Submission status: Wrong Answer

Solution code:
n, k = map(int, input().split())
a = [int(i) for i in input().split()]

l = [0]*n
x = [1]
w = 0
for i in range(k):
  l[x[i]-1] += 1
  w = a[x[i]-1]
  x.append(w)
  if l[w-1] == 1:
    break

c = 0
for i in range(k):
  if x[-1] == x[i]:
    c = i
    break

ans = (k-c)%(len(x)-1-c)    
print(x[i+ans])

Submission status: Wrong Answer

Solution code:
import sys
int1 = lambda x: int(x) - 1
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(500000)

N, K = map(int, readline().split())
A = list(map(int1, readline().split()))

visited = [0] * N
order = [0]
visited[0] = 1

pos = 0
while True:
    next_town = A[pos]
    
    if visited[next_town] == 1:
        order.append(next_town)
        break
    visited[next_town] += 1
    pos = next_town
    order.append(pos)

idx = order.index(order[-1])
l_l = len(order) - idx - 1
l = len(order) -1 - l_l

K -= l
K %= l_l

print(order[l+K]+1)

Submission status: Wrong Answer

Solution code:
"""
N towns
teleporter each town
teleporter at town i -> town A_i
k-times teleporter after starting at town 1
"""

from collections import deque

n, k = map(int, input().split())
a = list(map(lambda x: int(x) - 1, input().split()))

visited = [0] * n
path = deque()
cur = 0

while not visited[cur]:
    visited[cur] = 1
    path.append(cur)
    cur = a[cur]

while path[0] != cur and k > 0:
    k -= 1
    path.popleft()

#print(path)
if k == 0:
    print(path[0])
else:
    print((path[k % len(path)]) + 1)

Submission status: Wrong Answer

Solution code:
from collections import defaultdict as d 

n, k = map(int, input().split())
arr = list(map(int, input().split()))

s = '1'
i = 1
while True:
	if str(arr[i - 1]) in s:
		s += str(arr[i - 1])
		break
	s += str(arr[i - 1])
	i = arr[i - 1]

k %= len(s)
if k <= s.index(s[-1]):
	print(s[k])
else:
	k -= s.index(s[-1])
	x = len(s) - s.index(s[-1])
	print(s[s.index(s[-1]):][(k+1)%x])

Submission status: Wrong Answer

Solution code:
pi = 3.1415926

############ ---- USER DEFINED INPUT FUNCTIONS ---- ############
def inp():
    return(int(input().rstrip()))
def inlt():
    return(list(map(int,input().rstrip().split())))
def insr():
    s = input().rstrip()
    return(s[:len(s) - 1])
def invr():
    return(map(int,input().rstrip().split()))
################################################################
n,k = invr()
nums = [0] + inlt()
cycle = [nums[1]]

for i in range(2,n + 1):
    if nums[cycle[-1]] != cycle[0]:
        cycle.append(nums[cycle[-1]])
    else:
        break

if k <= len(cycle):
    print(cycle[k - 1])
else:
    remain = k % len(cycle)
    print(cycle[remain - (1 if remain >= 1 else 0)])

Submission status: Wrong Answer

Solution code:
N, K = map(int, input().split())
arr = list(map(int, input().split()))
check = [0]*N
index = 0
cnt = 0
while True:
    if cnt == K:
        print(index+1)
        exit()
    if check[index] == 1:
        break
    check[index] = 1
    index = arr[index]-1
    cnt += 1

index2 = 0
first_cnt = 0
while True:
    if index2 == index:
        break
    index2 = arr[index2]-1
    first_cnt += 1

if first_cnt == 0:
    ans_cnt = K % cnt
    index = 0
    cnt = 0
    while True:
        if cnt == ans_cnt:
            break
        index = arr[index]-1
        cnt += 1
    print(index+1)
else:
    ans_cnt = (K-first_cnt) % (cnt-first_cnt)
    index = 0
    cnt = 0
    while True:
        if cnt == first_cnt:
            break
        index = arr[index]-1
        cnt += 1
    print(index+1)

Submission status: Wrong Answer

Solution code:
N,K = map(int,input().split())
A = list(map(int,input().split()))

city = [-1 for i in range(0,N,1)]#0~N-1
count = 0
nex_city = 0
city[0]=0
while True:
    city[nex_city] = count
    nex_city = A[nex_city]-1
    count+=1
    if city[nex_city] >= 0:
        break

X = nex_city
Y = count - city[nex_city]

nex_city = 0
if K < X:
    for i in range(0,K,1):
        nex_city = A[nex_city]-1
    print(nex_city+1)
    exit()

nex_city = 0
for i in range(0,X+(K-X)%Y,1):
    nex_city = A[nex_city]-1

print(nex_city+1)

Submission status: Wrong Answer

Solution code:
# 2020-05-10
n, k = map(int, input().split())
lst = list(map(int, input().split()))
ans = 1
a = k % n
for i in range(a):
    b = lst[ans - 1]
    s = lst[b-1]
print(s)