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

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdlib>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string.h>
#include <string>
#include <utility>
#include <vector>

using namespace std;

/* template */

using ll = long long;

void debug_out() { std::cout << std::endl; }

template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) {
  cout << H << " ";
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...)                                                             \\
  cout << "debug: ";                                                           \\
  debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

#define rep(i, a, n) for (int i = (int)(a); i < (int)(n); i++)
#define rrep(i, a, n) for (int i = ((int)(n - 1)); i >= (int)(a); i--)
#define Rep(i, a, n) for (long long i = (long long)(a); i < (long long)(n); i++)
#define RRep(i, a, n)                                                          \\
  for (long long i = ((long long)(n - 1ll)); i >= (long long)(a); i--)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()

template <typename T>
std::ostream &operator<<(std::ostream &os, std::vector<T> vec) {
  for (std::size_t i = 0; i < vec.size(); i++)
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
  return os;
}

struct Edge {
  int to;
  ll weight;
  Edge(int t, ll w) : to(t), weight(w) {}
};

struct edge {
  int from;
  int to;
  ll weight;
  edge(int f, int t, ll w) : from(f), to(t), weight(w) {}
};

using Graph = vector<vector<Edge>>;
using graph = vector<vector<int>>;
using edges = vector<edge>;

template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

template <class T> T lcm(T a, T b) { return (a * b) / gcd(a, b); }

ll ctoi(char c) {
  switch (c) {
  case '0':
    return 0;
  case '1':
    return 1;
  case '2':
    return 2;
  case '3':
    return 3;
  case '4':
    return 4;
  case '5':
    return 5;
  case '6':
    return 6;
  case '7':
    return 7;
  case '8':
    return 8;
  case '9':
    return 9;
  default:
    return 0;
  }
}

constexpr ll LNF = 1LL << 50;

constexpr int INF = 1e9 + 7;

const long double PI = 3.14159265358979323846;

vector<int> dx = {1, 0, -1, 1, -1, 0};
vector<int> dy = {1, 1, 1, 0, 0, -1};

/* template */

int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  int d;
  cin >> d;
  vector<int> c(26);
  rep(i, 0, 26) cin >> c[i];
  vector<vector<ll>> s(d, vector<ll>(26));
  rep(i, 0, d) {
    rep(j, 0, 26) { cin >> s[i][j]; }
  }
  vector<int> t(d);
  rep(i, 0, d) { t[i] = rand() % 26; }
  ll ans = 0ll;
  vector<int> past(26, 0);
  vector<vector<int>> point(26, vector<int>(d));
  rep(i, 0, d) {
    past[t[i]] = i + 1;
    rep(j, 0, 26) {
      ans -= c[j] * (i + 1 - past[j]);
      point[j][i] = -c[j] * (i + 1 - past[j]);
    }
    ans += s[i][t[i]];
    point[t[i]][i] += s[i][t[i]];
  }
  int m = 100000;
  rep(_, 0, m) {
    int p = 1 + rand() % d;
    int q = 1 + rand() % 26;
    vector<int> tt = t;
    ll ord = ans;
    rep(i, p - 1, d) {
      if (i != p - 1 && point[t[p - 1]][i] > 0) {
        break;
      }
      ans -= point[t[p - 1]][i];
      point[t[p - 1]][i] = point[t[p - 1]][i - 1] - c[t[p - 1]];
      if (point[t[p - 1]][i - 1] > 0) {
        point[t[p - 1]][i] = -c[t[p - 1]];
      }
      ans += point[t[p - 1]][i];
    }
    t[p - 1] = q - 1;
    ans += s[p - 1][q - 1];
    ans -= point[q - 1][p - 1];
    point[q - 1][p - 1] = s[p - 1][q - 1];
    rep(i, p, d) {
      if (point[q - 1][i] > 0) {
        break;
      }
      ans -= point[q - 1][i];
      point[q - 1][i] = point[q - 1][i - 1] - c[q - 1];
      if (i == p) {
        point[q - 1][i] = -c[q - 1];
      }
      ans += point[q - 1][i];
    }
    if (ans < ord) {
      t = tt;
    }
  }
  rep(i, 0, d) { cout << t[i] + 1 << '\\n'; }
}

Error: WA

Fixed submission:

#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdlib>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string.h>
#include <string>
#include <utility>
#include <vector>

using namespace std;

/* template */

using ll = long long;

void debug_out() { std::cout << std::endl; }

template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) {
  cout << H << " ";
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...)                                                             \\
  cout << "debug: ";                                                           \\
  debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

#define rep(i, a, n) for (int i = (int)(a); i < (int)(n); i++)
#define rrep(i, a, n) for (int i = ((int)(n - 1)); i >= (int)(a); i--)
#define Rep(i, a, n) for (long long i = (long long)(a); i < (long long)(n); i++)
#define RRep(i, a, n)                                                          \\
  for (long long i = ((long long)(n - 1ll)); i >= (long long)(a); i--)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()

template <typename T>
std::ostream &operator<<(std::ostream &os, std::vector<T> vec) {
  for (std::size_t i = 0; i < vec.size(); i++)
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
  return os;
}

struct Edge {
  int to;
  ll weight;
  Edge(int t, ll w) : to(t), weight(w) {}
};

struct edge {
  int from;
  int to;
  ll weight;
  edge(int f, int t, ll w) : from(f), to(t), weight(w) {}
};

using Graph = vector<vector<Edge>>;
using graph = vector<vector<int>>;
using edges = vector<edge>;

template <class T> inline bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}

template <class T> inline bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

template <class T> T lcm(T a, T b) { return (a * b) / gcd(a, b); }

ll ctoi(char c) {
  switch (c) {
  case '0':
    return 0;
  case '1':
    return 1;
  case '2':
    return 2;
  case '3':
    return 3;
  case '4':
    return 4;
  case '5':
    return 5;
  case '6':
    return 6;
  case '7':
    return 7;
  case '8':
    return 8;
  case '9':
    return 9;
  default:
    return 0;
  }
}

constexpr ll LNF = 1LL << 50;

constexpr int INF = 1e9 + 7;

const long double PI = 3.14159265358979323846;

vector<int> dx = {1, 0, -1, 1, -1, 0};
vector<int> dy = {1, 1, 1, 0, 0, -1};

/* template */

int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  int d;
  cin >> d;
  vector<int> c(26);
  rep(i, 0, 26) cin >> c[i];
  vector<vector<ll>> s(d, vector<ll>(26));
  rep(i, 0, d) {
    rep(j, 0, 26) { cin >> s[i][j]; }
  }
  vector<int> t(d);
  rep(i, 0, d) { t[i] = rand() % d; }
  ll ans = 0ll;
  vector<int> past(26, 0);
  vector<vector<int>> point(26, vector<int>(d));
  rep(i, 0, d) {
    past[t[i]] = i + 1;
    rep(j, 0, 26) {
      ans -= c[j] * (i + 1 - past[j]);
      point[j][i] = -c[j] * (i + 1 - past[j]);
    }
    ans += s[i][t[i]];
    point[t[i]][i] += s[i][t[i]];
  }
  int m = 100;
  /*
  rep(_,0,m){
      int p = 1+ rand()%d;
      int q = 1+ rand()%26;
      vector<int> tt = t;
      ll ord = ans;
      rep(i,p-1,d){
          if(i!=p-1 && point[t[p-1]][i]>0){
              break;
          }
          ans -= point[t[p-1]][i];
          point[t[p-1]][i] = point[t[p-1]][i-1]-c[t[p-1]];
          if(point[t[p-1]][i-1]>0){
              point[t[p-1]][i] = -c[t[p-1]];
          }
          ans += point[t[p-1]][i];
      }
      t[p-1] = q-1;
      ans += s[p-1][q-1];
      ans -= point[q-1][p-1];
      point[q-1][p-1] = s[p-1][q-1];
      rep(i,p,d){
          if(point[q-1][i]>0){
              break;
          }
          ans -= point[q-1][i];
          point[q-1][i] = point[q-1][i-1]-c[q-1];
          if(i==p){
              point[q-1][i] = -c[q-1];
          }
          ans += point[q-1][i];
      }
      if(ans<ord){
          t = tt;
      }
  }
  */
  rep(i, 0, d) { cout << t[i] + 1 << '\\n'; }
}