Problem p02647 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = double;
using ld = long double;
template <typename T> using V = vector<T>;
template <typename T> using VV = vector<vector<T>>;
#define fs first
#define sc second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define all(v) (v).begin(), (v).end()
#define siz(v) (ll)(v).size()
#define rep(i, a, n) for (ll i = a; i < (ll)(n); ++i)
#define repr(i, a, n) for (ll i = n - 1; (ll)a <= i; --i)
#define ENDL '\\n'
typedef pair<int, int> Pi;
typedef pair<ll, ll> PL;
constexpr ll mod = 1000000007;
constexpr ll INF = 1000000099;
constexpr ll LINF = (ll)(1e18 + 99);
const vector<ll> dx = {-1, 1, 0, 0}, dy = {0, 0, -1, 1};
template <typename T, typename U> inline bool chmin(T &t, const U &u) {
  if (t > u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T, typename U> inline bool chmax(T &t, const U &u) {
  if (t < u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T> inline T gcd(T a, T b) { return b ? gcd(b, a % b) : a; }

template <typename T, typename Y> inline T mpow(T a, Y n) {
  T res = 1;
  for (; n; n >>= 1) {
    if (n & 1)
      res = res * a;
    a = a * a;
  }
  return res;
}

template <typename T, typename Y>
ostream &operator<<(ostream &os, const pair<T, Y> &p) {
  return os << "{" << p.fs << "," << p.sc << "}";
}
template <typename T> ostream &operator<<(ostream &os, const V<T> &v) {
  os << "{";
  for (auto e : v)
    os << e << ",";
  return os << "}";
}
template <typename... Args> void debug(Args &...args) {
  for (auto const &x : {args...}) {
    cerr << x << ' ';
  }
  cerr << ENDL;
}

ll dp[50][200010] = {};

signed main() {
  cin.tie(0);
  cerr.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(20);
  ll n, k;
  cin >> n >> k;
  V<ll> a(n + 1, 0), b(n + 1, 0);
  rep(i, 0, n) cin >> dp[0][i];

  rep(j, 0, k) {
    rep(i, 0, n) {
      dp[j + 1][max(0ll, i - dp[j][i])]++;
      dp[j + 1][min(n, i + dp[j][i] + 1)]--;
    }

    bool up = false;
    rep(i, 0, n) {
      dp[j + 1][i + 1] += dp[j + 1][i];
      if (dp[j + 1][i] < n)
        up = true;
    }

    if (!up) {
      cerr << j << ENDL;
      rep(i, 0, n) { cout << dp[j + 1][i] << " "; }
      cout << ENDL;
      return 0;
    }
  }

  rep(i, 0, n) { cout << dp[k][i] << " "; }
  cout << ENDL;
}
//! ( . _ . ) !
// CHECK overflow,vector_size,what to output?

Error: WA

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = double;
using ld = long double;
template <typename T> using V = vector<T>;
template <typename T> using VV = vector<vector<T>>;
#define fs first
#define sc second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define all(v) (v).begin(), (v).end()
#define siz(v) (ll)(v).size()
#define rep(i, a, n) for (ll i = a; i < (ll)(n); ++i)
#define repr(i, a, n) for (ll i = n - 1; (ll)a <= i; --i)
#define ENDL '\\n'
typedef pair<int, int> Pi;
typedef pair<ll, ll> PL;
constexpr ll mod = 1000000007;
constexpr ll INF = 1000000099;
constexpr ll LINF = (ll)(1e18 + 99);
const vector<ll> dx = {-1, 1, 0, 0}, dy = {0, 0, -1, 1};
template <typename T, typename U> inline bool chmin(T &t, const U &u) {
  if (t > u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T, typename U> inline bool chmax(T &t, const U &u) {
  if (t < u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T> inline T gcd(T a, T b) { return b ? gcd(b, a % b) : a; }

template <typename T, typename Y> inline T mpow(T a, Y n) {
  T res = 1;
  for (; n; n >>= 1) {
    if (n & 1)
      res = res * a;
    a = a * a;
  }
  return res;
}

template <typename T, typename Y>
ostream &operator<<(ostream &os, const pair<T, Y> &p) {
  return os << "{" << p.fs << "," << p.sc << "}";
}
template <typename T> ostream &operator<<(ostream &os, const V<T> &v) {
  os << "{";
  for (auto e : v)
    os << e << ",";
  return os << "}";
}
template <typename... Args> void debug(Args &...args) {
  for (auto const &x : {args...}) {
    cerr << x << ' ';
  }
  cerr << ENDL;
}

ll dp[50][200010] = {};

signed main() {
  cin.tie(0);
  cerr.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(20);
  ll n, k;
  cin >> n >> k;
  V<ll> a(n + 1, 0), b(n + 1, 0);
  rep(i, 0, n) cin >> dp[0][i];

  rep(j, 0, k) {
    rep(i, 0, n) {
      dp[j + 1][max(0ll, i - dp[j][i])]++;
      dp[j + 1][min(n, i + dp[j][i] + 1)]--;
    }

    bool up = false;
    rep(i, 0, n) {
      dp[j + 1][i + 1] += dp[j + 1][i];
      if (dp[j + 1][i] < k)
        up = true;
    }

    if (!up) {
      rep(i, 0, n) { cout << dp[j + 1][i] << " "; }
      cout << ENDL;
      return 0;
    }
  }

  rep(i, 0, n) { cout << dp[k][i] << " "; }
  cout << ENDL;
}
//! ( . _ . ) !
// CHECK overflow,vector_size,what to output?