Buggy python submission (verdict: Time Limit Exceeded):
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = [i - 1 for i in map(int, readline().split())]

m = 64
d = [A]
pre = A
for i in range(m):
    current = [pre[pre[j]] for j in range(n)]
    d.append(current)
    pre = current

route = 0
for i in range(m-1, -1, -1):
    if k >= (x := 1 << i):
        route = d[i][route]
        k -= x
print(route+1)


Fixed submission:
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])

Buggy python submission (verdict: Runtime Error):
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k-1:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])


Fixed submission:
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])

Buggy python submission (verdict: Runtime Error):
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) >= k-1:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])


Fixed submission:
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])

Buggy python submission (verdict: Runtime Error):
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(x)
print(l[x-1:][(k-l.index(x)) % len(l[x-1:])])


Fixed submission:
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])

Buggy python submission (verdict: Runtime Error):
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

l = [1]
while True:
    x = A[l[-1]-1]
    if x in l:
        break
    l.append(x)
print(l[x-1:][k % len(l)])


Fixed submission:
import sys

readline = sys.stdin.readline
n, k = map(int, readline().split())
A = list(map(int, readline().split()))

visited = [False] * n
visited[0] = True
l = [1]
while True:
    x = A[l[-1]-1]
    if visited[x-1]:
        break
    l.append(x)
    visited[x-1] = True
# print(l[l.index(x):])
if len(l) > k:
    print(l[k])
else:
    print(l[l.index(x):][(k-l.index(x)) % len(l[l.index(x):])])