Problem p02684 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef tree<pair<int, int>, null_type, less<pair<int, int>>, rb_tree_tag,
             tree_order_statistics_node_update>
    oset;
#define sim template <class c
#define ris return *this
#define dor > debug &operator<<
#define eni(x)                                                                 \\
  sim > typename enable_if<sizeof dud<c>(0) x 1, debug &>::type operator<<(    \\
            c i) {
sim > struct rge {
  c b, e;
};
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c *x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
  ~debug() { cerr << endl; }
  eni(!=) cerr << boolalpha << i;
  ris;
} eni(==) ris << range(begin(i), end(i));
}
sim, class b dor(pair<b, c> d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
  sim dor(const c &) { ris; }
#endif
}
;
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
using ll = long long;

const int D = 60;
const int MAX_N = 200005;
int to[D][MAX_N];

void test_case() {
  ll n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) {
    cin >> to[0][i];
    to[0][i]--;
  }
  for (int i = 0; i < D - 1; i++) {
    for (int j = 0; j < n; j++) {
      to[i + 1][j] = to[i][to[i][j]];
    }
  }

  int v = 0;
  for (int i = D - 1; i >= 0; --i) {
    ll l = 1ll << i;
    if (l <= k) {
      v = to[i][v];
      k -= l;
    }
  }
  cout << v + 1 << "\\n";
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int T = 1;
  //~ cin >> T;
  while (T--) {
    test_case();
  }
  return 0;
}


Error: -11

Fixed submission:

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef tree<pair<int, int>, null_type, less<pair<int, int>>, rb_tree_tag,
             tree_order_statistics_node_update>
    oset;
#define sim template <class c
#define ris return *this
#define dor > debug &operator<<
#define eni(x)                                                                 \\
  sim > typename enable_if<sizeof dud<c>(0) x 1, debug &>::type operator<<(    \\
            c i) {
sim > struct rge {
  c b, e;
};
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c *x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
  ~debug() { cerr << endl; }
  eni(!=) cerr << boolalpha << i;
  ris;
} eni(==) ris << range(begin(i), end(i));
}
sim, class b dor(pair<b, c> d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
  sim dor(const c &) { ris; }
#endif
}
;
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
using ll = long long;

const int D = 60;
const int MAX_N = 200005;
int to[D][MAX_N];

void test_case() {
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) {
    cin >> to[0][i];
    to[0][i]--;
  }
  for (int i = 0; i < D - 1; i++) {
    for (int j = 0; j < n; j++) {
      to[i + 1][j] = to[i][to[i][j]];
    }
  }

  int v = 0;
  for (int i = D - 1; i >= 0; --i) {
    ll l = 1ll << i;
    if (l <= k) {
      v = to[i][v];
      k -= 1;
    }
  }
  cout << v + 1 << "\\n";
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int T;
  cin >> T;
  while (T--) {
    test_case();
  }
  return 0;
}