Problem p02962 (C++)

Buggy submission (status: Runtime Error):
#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <deque>
#include <iostream>
#include <iterator>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#define FOR(i, k, n) for (int(i) = (k); (i) < (n); ++(i))
#define rep(i, n) FOR(i, 0, n)
#define all(v) begin(v), end(v)
#define debug(x)     // std::cerr<<#x<<": "<<x<<"\n"
#define debug2(x, y) // std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<"\n"
#define debug3(                                                                \
    x, y,                                                                      \
    z) // std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<", "<<#z<<": "<<z<<"\n"

using ll = long long;
using vi = std::vector<int>;
using vvi = std::vector<vi>;
using vll = std::vector<ll>;
using vvll = std::vector<vll>;
template <typename T> using vvec = std::vector<std::vector<T>>;
template <typename T> auto make_v(size_t sz) { return std::vector<T>(sz); }
template <typename T, typename... Ts> auto make_v(size_t sz, Ts... ts) {
  return std::vector<decltype(make_v<T>(ts...))>(sz, make_v<T>(ts...));
}
template <typename T> void fill_v(T &var, const T &x) { var = x; }
template <typename V, typename T> void fill_v(V &v, const T &x) {
  for (auto &&w : v) {
    fill_v(w, x);
  }
}

template <typename T>
std::ostream &operator<<(std::ostream &s, const std::vector<T> &v) {
  int sz = v.size();
  s << "\n";
  rep(i, sz) {
    s << v[i];
    if (i < sz - 1) {
      s << "\t";
    }
  }
  s << "\n";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s,
                         const std::vector<std::vector<T>> &v) {
  for (auto &&w : v) {
    s << w;
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::deque<T> &v) {
  int sz = v.size();
  s << "\n";
  rep(i, sz) {
    s << v[i];
    if (i < sz - 1) {
      s << "\t";
    }
  }
  s << "\n";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::deque<std::deque<T>> &v) {
  for (auto &&w : v) {
    s << w;
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::set<T> &v) {
  s << "\n";
  for (auto &&elm : v) {
    s << elm << "\t";
  }
  s << "\n";
  return s;
}

inline void scan(int &a) { scanf("%d", &a); }
inline void scan(ll &a) { scanf("%lld", &a); }
inline void scan(char &a) { scanf(" %c", &a); }
inline void scan(double &a) { scanf("%lf", &a); }
inline void scan(std::string &s) {
  char BUF[3000000];
  scanf(" %s", BUF);
  s = std::string(BUF);
}
template <typename T> inline void scan(std::vector<T> &v) {
  for (auto &&sv : v) {
    scan(sv);
  }
}
template <typename First, typename... Args>
inline void scan(First &f, Args &...args) {
  scan(f);
  scan(args...);
}
inline void print(int a) { printf("%d\n", a); }
inline void print(ll a) { printf("%lld\n", a); }
inline void print(double a) { printf("%.12f\n", a); }
inline void print(std::string s) { std::cout << s << "\n"; }

using namespace std;

class RollingHash {
  using ll = long long;

private:
  std::vector<ll> data;
  ll base;
  std::vector<ll> mod;
  std::vector<std::vector<ll>> power_base;
  std::vector<std::vector<ll>> hash;

  void assign_base() {
    std::random_device rnd;
    std::mt19937 mt(rnd());
    base = mt() % (mod[0] - 3) + 2;
  }
  void assign_hash() {
    power_base.assign(data.size(), std::vector<ll>(mod.size(), 0));
    for (size_t i = 0; i < mod.size(); ++i) {
      power_base[0][i] = 1;
    }
    for (size_t i = 0; i < data.size() - 1; ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        power_base[i + 1][j] = power_base[i][j] * base % mod[j];
      }
    }
    hash.assign(data.size() + 1, std::vector<ll>(mod.size(), 0));
    for (size_t i = 0; i < data.size(); ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        hash[i + 1][j] = (hash[i][j] + data[i] * power_base[i][j]) % mod[j];
      }
    }
  }

public:
  RollingHash() {}
  RollingHash(std::vector<ll> &v) : data(v) {
    mod = {1000000007, 1000000009, 1000000021, 1000000087};
    assign_base();
    assign_hash();
  }
  RollingHash(std::vector<ll> &v, std::vector<ll> &m) : data(v), mod(m) {
    std::sort(std::begin(mod), std::end(mod));
    assign_base();
    assign_hash();
  }

  std::vector<int> include(std::vector<ll> data2) {
    std::vector<int> ret;
    if (data.size() < data2.size()) {
      return ret;
    }
    std::vector<ll> hash2(mod.size(), 0);
    for (size_t i = 0; i < data2.size(); ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        hash2[j] = (hash2[j] + data2[i] * power_base[i][j]) % mod[j];
      }
    }
    for (size_t i = 0; i < data.size() - data2.size() + 1; ++i) {
      bool flag = true;
      for (size_t j = 0; j < mod.size(); ++j) {
        if (hash[i + data2.size()][j] !=
            (hash[i][j] + hash2[j] * power_base[i][j]) % mod[j]) {
          flag = false;
          break;
        }
      }
      if (flag) {
        ret.push_back(i);
      }
    }
    return ret;
  }
};

int main() {
  string s, t;
  scan(s);
  scan(t);
  int sl = s.length();
  int tl = t.length();
  string x;
  int scnt = (sl + tl - 2 + sl - 1) / sl;
  rep(i, scnt) { x += s; }
  int xl = x.length();
  vll vx(xl, 0);
  rep(i, xl) { vx[i] = x[i] - '/'; }
  vll vt(tl, 0);
  rep(i, tl) { vt[i] = t[i] - '/'; }

  RollingHash rh(vx);
  auto match = rh.include(vt);
  debug(x);
  debug(t);
  debug(match);

  vi g(sl, -1);
  vi dig_in(sl, 0);
  for (int ind : match) {
    if (ind >= sl) {
      break;
    }
    g[ind] = (ind + tl) % sl;
    dig_in[g[ind]] += 1;
  }

  int ans = 0;
  vector<bool> arrived(sl, false);
  rep(i, sl) {
    if (dig_in[i] > 0) {
      continue;
    }
    set<int> si;
    int current_index = i;
    si.insert(current_index);
    arrived[current_index] = true;
    while (true) {
      int next_index = g[current_index];
      if (next_index == -1) {
        break;
      }
      current_index = next_index;
      si.insert(current_index);
      arrived[current_index] = true;
    }
    ans = max(ans, (int)si.size() - 1);
  }
  rep(i, sl) {
    if (!arrived[i]) {
      ans = -1;
      break;
    }
  }
  print(ans);

  return 0;
}


Fixed submission:
#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <deque>
#include <iostream>
#include <iterator>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#define FOR(i, k, n) for (int(i) = (k); (i) < (n); ++(i))
#define rep(i, n) FOR(i, 0, n)
#define all(v) begin(v), end(v)
#define debug(x)     // std::cerr<<#x<<": "<<x<<"\n"
#define debug2(x, y) // std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<"\n"
#define debug3(                                                                \
    x, y,                                                                      \
    z) // std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<", "<<#z<<": "<<z<<"\n"

using ll = long long;
using vi = std::vector<int>;
using vvi = std::vector<vi>;
using vll = std::vector<ll>;
using vvll = std::vector<vll>;
template <typename T> using vvec = std::vector<std::vector<T>>;
template <typename T> auto make_v(size_t sz) { return std::vector<T>(sz); }
template <typename T, typename... Ts> auto make_v(size_t sz, Ts... ts) {
  return std::vector<decltype(make_v<T>(ts...))>(sz, make_v<T>(ts...));
}
template <typename T> void fill_v(T &var, const T &x) { var = x; }
template <typename V, typename T> void fill_v(V &v, const T &x) {
  for (auto &&w : v) {
    fill_v(w, x);
  }
}

template <typename T>
std::ostream &operator<<(std::ostream &s, const std::vector<T> &v) {
  int sz = v.size();
  s << "\n";
  rep(i, sz) {
    s << v[i];
    if (i < sz - 1) {
      s << "\t";
    }
  }
  s << "\n";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s,
                         const std::vector<std::vector<T>> &v) {
  for (auto &&w : v) {
    s << w;
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::deque<T> &v) {
  int sz = v.size();
  s << "\n";
  rep(i, sz) {
    s << v[i];
    if (i < sz - 1) {
      s << "\t";
    }
  }
  s << "\n";
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::deque<std::deque<T>> &v) {
  for (auto &&w : v) {
    s << w;
  }
  return s;
}
template <typename T>
std::ostream &operator<<(std::ostream &s, const std::set<T> &v) {
  s << "\n";
  for (auto &&elm : v) {
    s << elm << "\t";
  }
  s << "\n";
  return s;
}

inline void scan(int &a) { scanf("%d", &a); }
inline void scan(ll &a) { scanf("%lld", &a); }
inline void scan(char &a) { scanf(" %c", &a); }
inline void scan(double &a) { scanf("%lf", &a); }
inline void scan(std::string &s) {
  char BUF[3000000];
  scanf(" %s", BUF);
  s = std::string(BUF);
}
template <typename T> inline void scan(std::vector<T> &v) {
  for (auto &&sv : v) {
    scan(sv);
  }
}
template <typename First, typename... Args>
inline void scan(First &f, Args &...args) {
  scan(f);
  scan(args...);
}
inline void print(int a) { printf("%d\n", a); }
inline void print(ll a) { printf("%lld\n", a); }
inline void print(double a) { printf("%.12f\n", a); }
inline void print(std::string s) { std::cout << s << "\n"; }

using namespace std;

class RollingHash {
  using ll = long long;

private:
  std::vector<ll> data;
  ll base;
  std::vector<ll> mod;
  std::vector<std::vector<ll>> power_base;
  std::vector<std::vector<ll>> hash;

  void assign_base() {
    std::random_device rnd;
    std::mt19937 mt(rnd());
    base = mt() % (mod[0] - 3) + 2;
  }
  void assign_hash() {
    power_base.assign(data.size(), std::vector<ll>(mod.size(), 0));
    for (size_t i = 0; i < mod.size(); ++i) {
      power_base[0][i] = 1;
    }
    for (size_t i = 0; i < data.size() - 1; ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        power_base[i + 1][j] = power_base[i][j] * base % mod[j];
      }
    }
    hash.assign(data.size() + 1, std::vector<ll>(mod.size(), 0));
    for (size_t i = 0; i < data.size(); ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        hash[i + 1][j] = (hash[i][j] + data[i] * power_base[i][j]) % mod[j];
      }
    }
  }

public:
  RollingHash() {}
  RollingHash(std::vector<ll> &v) : data(v) {
    mod = {1000000007, 1000000009, 1000000021, 1000000087};
    assign_base();
    assign_hash();
  }
  RollingHash(std::vector<ll> &v, std::vector<ll> &m) : data(v), mod(m) {
    std::sort(std::begin(mod), std::end(mod));
    assign_base();
    assign_hash();
  }

  std::vector<int> include(std::vector<ll> data2) {
    std::vector<int> ret;
    if (data.size() < data2.size()) {
      return ret;
    }
    std::vector<ll> hash2(mod.size(), 0);
    for (size_t i = 0; i < data2.size(); ++i) {
      for (size_t j = 0; j < mod.size(); ++j) {
        hash2[j] = (hash2[j] + data2[i] * power_base[i][j]) % mod[j];
      }
    }
    for (size_t i = 0; i < data.size() - data2.size() + 1; ++i) {
      bool flag = true;
      for (size_t j = 0; j < mod.size(); ++j) {
        if (hash[i + data2.size()][j] !=
            (hash[i][j] + hash2[j] * power_base[i][j]) % mod[j]) {
          flag = false;
          break;
        }
      }
      if (flag) {
        ret.push_back(i);
      }
    }
    return ret;
  }
};

int main() {
  string s, t;
  scan(s);
  scan(t);
  int sl = s.length();
  int tl = t.length();
  string x;
  int scnt = (sl + tl - 1 + sl - 1) / sl;
  rep(i, scnt) { x += s; }
  int xl = x.length();
  vll vx(xl, 0);
  rep(i, xl) { vx[i] = x[i] - '/'; }
  vll vt(tl, 0);
  rep(i, tl) { vt[i] = t[i] - '/'; }

  RollingHash rh(vx);
  auto match = rh.include(vt);
  debug(x);
  debug(t);
  debug(match);

  vi g(sl, -1);
  vi dig_in(sl, 0);
  for (int ind : match) {
    if (ind >= sl) {
      break;
    }
    g[ind] = (ind + tl) % sl;
    dig_in[g[ind]] += 1;
  }

  int ans = 0;
  vector<bool> arrived(sl, false);
  rep(i, sl) {
    if (dig_in[i] > 0) {
      continue;
    }
    set<int> si;
    int current_index = i;
    si.insert(current_index);
    arrived[current_index] = true;
    while (true) {
      int next_index = g[current_index];
      if (next_index == -1) {
        break;
      }
      current_index = next_index;
      si.insert(current_index);
      arrived[current_index] = true;
    }
    ans = max(ans, (int)si.size() - 1);
  }
  rep(i, sl) {
    if (!arrived[i]) {
      ans = -1;
      break;
    }
  }
  print(ans);

  return 0;
}