Problem p02618 (C++) — buggy submission, verdict: Runtime Error

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <ctime>
#include <deque>
#include <float.h>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#pragma warning(disable : 4996)
using namespace std;

using ll = long long;
unsigned euclidean_gcd(unsigned a, unsigned b) {
  if (a < b)
    return euclidean_gcd(b, a);
  unsigned r;
  while ((r = a % b)) {
    a = b;
    b = r;
  }
  return b;
}

ll ll_gcd(ll a, ll b) {
  if (a < b)
    return ll_gcd(b, a);
  ll r;
  while ((r = a % b)) {
    a = b;
    b = r;
  }
  return b;
}

struct UnionFind {
  vector<ll> par;
  vector<ll> siz;
  UnionFind(ll sz_) : par(sz_), siz(sz_, 1LL) {
    for (ll i = 0; i < sz_; ++i)
      par[i] = i;
  }
  void init(ll sz_) {
    par.resize(sz_);
    siz.assign(sz_, 1LL);
    for (ll i = 0; i < sz_; ++i)
      par[i] = i;
  }
  ll root(ll x) {
    while (par[x] != x) {
      x = par[x] = par[par[x]];
    }
    return x;
  }
  bool merge(ll x, ll y) {
    x = root(x);
    y = root(y);
    if (x == y)
      return false;
    if (siz[x] < siz[y])
      swap(x, y);
    siz[x] += siz[y];
    par[y] = x;
    return true;
  }

  bool issame(ll x, ll y) { return root(x) == root(y); }

  ll size(ll x) { return siz[root(x)]; }
};

long long modpow(long long a, long long n, long long mod) {
  if (n < 0)
    return 0;
  long long res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}

long long modinv(long long a, long long mod) { return modpow(a, mod - 2, mod); }

ll merge_cnt(vector<ll> &a) {
  int n = a.size();
  if (n <= 1) {
    return 0;
  }

  ll cnt = 0;
  vector<ll> b(a.begin(), a.begin() + n / 2);
  vector<ll> c(a.begin() + n / 2, a.end());

  cnt += merge_cnt(b);
  cnt += merge_cnt(c);

  int ai = 0, bi = 0, ci = 0;
  while (ai < n) {
    if (bi < b.size() && (ci == c.size() || b[bi] <= c[ci])) {
      a[ai++] = b[bi++];
    } else {
      cnt += n / 2 - bi;
      a[ai++] = c[ci++];
    }
  }
  return cnt;
}

struct edge {
  ll to, cost;
};
typedef pair<ll, ll> P;
struct graph {
  ll V;
  vector<vector<edge>> G;
  vector<ll> d;

  graph(ll n) { init(n); }

  void init(ll n) {
    V = n;
    G.resize(V);
    d.resize(V);
    for (int i = 0; i < V; i++) {
      d[i] = 2000000000000000000;
    }
  }

  void add_edge(ll s, ll t, ll cost) {
    edge e;
    e.to = t, e.cost = cost;
    G[s].push_back(e);
  }

  void dijkstra(ll s) {
    for (int i = 0; i < V; i++) {
      d[i] = 2000000000000000000;
    }
    d[s] = 0;
    priority_queue<P, vector<P>, greater<P>> que;
    que.push(P(0, s));
    while (!que.empty()) {
      P p = que.top();
      que.pop();
      ll v = p.second;
      if (d[v] < p.first)
        continue;
      for (auto e : G[v]) {
        if (d[e.to] > d[v] + e.cost) {
          d[e.to] = d[v] + e.cost;
          que.push(P(d[e.to], e.to));
        }
      }
    }
  }
};

int main() {
  int d;
  cin >> d;
  vector<int> z(26);
  for (int i = 0; i < 26; i++) {
    cin >> z[i];
  }
  vector<vector<int>> s(26, vector<int>(d));
  for (int i = 0; i < d; i++) {
    for (int j = 0; j < 26; j++) {
      cin >> s[j][i];
    }
  }
  vector<int> ans(d);
  for (int i = 0; i < d; i++) {
    ans[i] = rand() % 26;
  }
  int zans = 0;
  for (int i = 0; i < 26; i++) {
    ll t = 0;
    for (int j = 0; j < d; j++) {
      if (i == ans[j]) {
        zans += s[i][j];
        t = 0;
      } else {
        t++;
      }
      zans -= t * z[i];
    }
  }
  vector<set<int>> st(26);
  for (int i = 0; i < 26; i++) {
    st[i].insert(-1);
    st[i].insert(d);
  }
  for (int i = 0; i < d; i++) {
    st[ans[i]].insert(i);
  }
  for (int i = 0; i < 400000; i++) {
    int a, b;
    a = rand() % d;
    b = rand() % 26;
    int zzans = zans;
    zzans += s[b][a];
    zzans -= s[ans[a]][a];
    st[ans[a]].erase(a);
    auto f = st[ans[a]].lower_bound(a);
    int g = *f;
    f--;
    int h = *f;
    zans -= ((g - h) * (g - h - 1) / 2 - (g - a) * (g - a - 1) / 2 -
             (a - h) * (a - h - 1) / 2) *
            z[ans[a]];
    f = st[b].lower_bound(a);
    g = *f;
    f--;
    h = *f;
    zans += ((g - h) * (g - h - 1) / 2 - (g - a) * (g - a - 1) / 2 -
             (a - h) * (a - h - 1) / 2) *
            z[b];

    if (zzans >= zans) {
      st[b].insert(a);
      ans[a] = b;
    } else {
      st[ans[a]].insert(a);
    }
  }
  for (int i = 0; i < d; i++) {
    cout << ans[i] + 1 << endl;
  }
}

Error: -11

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <ctime>
#include <deque>
#include <float.h>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using ll = long long;
unsigned euclidean_gcd(unsigned a, unsigned b) {
  if (a < b)
    return euclidean_gcd(b, a);
  unsigned r;
  while ((r = a % b)) {
    a = b;
    b = r;
  }
  return b;
}

ll ll_gcd(ll a, ll b) {
  if (a < b)
    return ll_gcd(b, a);
  ll r;
  while ((r = a % b)) {
    a = b;
    b = r;
  }
  return b;
}

class UnionFind {
public:
  vector<ll> par;
  vector<ll> siz;
  UnionFind(ll sz_) : par(sz_), siz(sz_, 1LL) {
    for (ll i = 0; i < sz_; ++i)
      par[i] = i;
  }
  void init(ll sz_) {
    par.resize(sz_);
    siz.assign(sz_, 1LL);
    for (ll i = 0; i < sz_; ++i)
      par[i] = i;
  }
  ll root(ll x) {
    while (par[x] != x) {
      x = par[x] = par[par[x]];
    }
    return x;
  }
  bool merge(ll x, ll y) {
    x = root(x);
    y = root(y);
    if (x == y)
      return false;
    if (siz[x] < siz[y])
      swap(x, y);
    siz[x] += siz[y];
    par[y] = x;
    return true;
  }

  bool issame(ll x, ll y) { return root(x) == root(y); }

  ll size(ll x) { return siz[root(x)]; }
};

long long modpow(long long a, long long n, long long mod) {
  long long res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}

long long modinv(long long a, long long mod) { return modpow(a, mod - 2, mod); }

int main() {
  ll d;
  cin >> d;
  vector<ll> z(26);
  for (int i = 0; i < 26; i++) {
    cin >> z[i];
  }
  vector<vector<ll>> x(d, vector<ll>(26));
  for (int i = 0; i < d; i++) {
    for (int j = 0; j < 26; j++) {
      cin >> x[i][j];
    }
  }
  vector<ll> ans(d, 1);
  for (int i = 0; i < 14; i++) {
    vector<bool> flag(26, false);
    for (int j = 0; j < 26; j++) {
      ll mx = 0;
      ll atai = 0;
      for (int k = 0; k < 26; k++) {
        if (flag[k] == false) {
          mx = max(x[i * 26 + j][k], mx);
          if (mx == x[i * 26 + j][k])
            atai = k;
        }
      }
      flag[atai] = true;
      ans[i * 26 + j] = atai + 1;
    }
  }
  ll mix = 0;
  ll ataii = 0;
  for (int k = 0; k < 26; k++) {
    mix = max(x[364][k], mix);
    if (mix == x[364][k])
      ataii = k;
  }
  ans[364] = ataii + 1;

  for (int h = 0; h < 23; h++) {
    for (int i = 0; i < d - (h % 3); i++) {
      if (x[i][ans[i] - 1] < x[i][ans[i + (h % 3 + 1)] - 1] &&
          x[i + (h % 3 + 1)][ans[i + (h % 3 + 1)] - 1] <
              x[i + (h % 3 + 1)][ans[i] - 1]) {
        ll b = ans[i + (h % 3 + 1)];
        ans[i + (h % 3 + 1)] = ans[i];
        ans[i] = b;
      }
    }
  }
  for (int i = 0; i < d; i++) {
    cout << ans[i] << endl;
  }
}