Problem p04022 (C++)

Buggy submission (status: Runtime Error):
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)n; i++)
#define all(c) (c).begin(), (c).end()
#define pb push_back
#define dbg(...)                                                               \
  do {                                                                         \
    cerr << __LINE__ << ": ";                                                  \
    dbgprint(#__VA_ARGS__, __VA_ARGS__);                                       \
  } while (0);

using namespace std;

namespace std {
template <class S, class T> struct hash<pair<S, T>> {
  size_t operator()(const pair<S, T> &p) const {
    return ((size_t)1e9 + 7) * hash<S>()(p.first) + hash<T>()(p.second);
  }
};
template <class T> struct hash<vector<T>> {
  size_t operator()(const vector<T> &v) const {
    size_t h = 0;
    for (auto i : v)
      h = h * ((size_t)1e9 + 7) + hash<T>()(i) + 1;
    return h;
  }
};
} // namespace std
template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << "[ ";
  rep(i, v.size()) os << v[i] << (i == v.size() - 1 ? " ]" : ", ");
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << "{ ";
  for (const auto &i : v)
    os << i << ", ";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &v) {
  os << "{";
  for (const auto &i : v)
    os << " " << i.first << ": " << i.second << ",";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << "(" << p.first << ", " << p.second << ")";
}
void dbgprint(const string &fmt) { cerr << endl; }
template <class H, class... T>
void dbgprint(const string &fmt, const H &h, const T &...r) {
  cerr << fmt.substr(0, fmt.find(",")) << "= " << h << " ";
  dbgprint(fmt.substr(fmt.find(",") + 1), r...);
}
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = (int)1e9;
const double INF = 1e12, EPS = 1e-9;

const int MX = 3000;
bool p[MX];
int n;
ll s[MX];
map<ll, int> sqs;

vector<ll> comp(const vector<ll> &m) {
  if (m.size() == 0)
    return m;
  vector<ll> res;
  rep(i, m.size()) {
    if (m[i] >= MX) {
      if (sqs.count(m[i]))
        res.pb(sqs[m[i]]);
      else
        res.pb(m[i] * m[i]);
      continue;
    }
    if (i + 1 < m.size() && m[i] == m[i + 1])
      res.pb(m[i++]);
    else {
      res.pb(m[i]);
      res.pb(m[i]);
    }
  }
  return res;
}

int main() {
  cin.tie(0);
  cin.sync_with_stdio(0);
  vi prime;
  for (int i = 2; i * i < MX; i++)
    if (!p[i])
      for (int j = i * i; j < MX; j += i)
        p[j] = 1;
  for (int i = 2; i < MX; i++)
    if (!p[i])
      prime.pb(i);
  for (ll i = 1; i * i <= 1e10; i++)
    sqs[i * i] = i;

  cin >> n;
  rep(i, n) cin >> s[i];
  map<vector<ll>, int> M;
  set<vector<ll>> done;
  int ans = 0;

  rep(ii, n) {
    ll m = s[ii];
    vector<ll> v;

    for (int i = 0; i < prime.size() && (ll)prime[i] * prime[i] <= m; i++)
      if (m % prime[i] == 0) {
        int cnt = 0;
        for (; m % prime[i] == 0; cnt++)
          m /= prime[i];
        cnt %= 3;
        rep(it, cnt) v.pb(prime[i]);
      }
    if (m > 1)
      v.pb(m);
    sort(all(v));
    M[v]++;
  }

  done.insert(vector<ll>());
  for (auto m : M) {
    if (done.count(m.first))
      continue;
    auto mm = comp(m.first);

    if (M.count(mm)) {
      int l = m.second, r = M[mm];
      ans += max(l, r);
      done.insert(mm);
    } else
      ans += m.second;
  }
  if (M.count(vector<ll>()))
    ans++;
  cout << ans << endl;
  return 0;
}

Fixed submission:
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)n; i++)
#define all(c) (c).begin(), (c).end()
#define pb push_back
#define dbg(...)                                                               \
  do {                                                                         \
    cerr << __LINE__ << ": ";                                                  \
    dbgprint(#__VA_ARGS__, __VA_ARGS__);                                       \
  } while (0);

using namespace std;

namespace std {
template <class S, class T> struct hash<pair<S, T>> {
  size_t operator()(const pair<S, T> &p) const {
    return ((size_t)1e9 + 7) * hash<S>()(p.first) + hash<T>()(p.second);
  }
};
template <class T> struct hash<vector<T>> {
  size_t operator()(const vector<T> &v) const {
    size_t h = 0;
    for (auto i : v)
      h = h * ((size_t)1e9 + 7) + hash<T>()(i) + 1;
    return h;
  }
};
} // namespace std
template <class T> ostream &operator<<(ostream &os, const vector<T> &v) {
  os << "[ ";
  rep(i, v.size()) os << v[i] << (i == v.size() - 1 ? " ]" : ", ");
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &v) {
  os << "{ ";
  for (const auto &i : v)
    os << i << ", ";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const map<T, U> &v) {
  os << "{";
  for (const auto &i : v)
    os << " " << i.first << ": " << i.second << ",";
  return os << "}";
}
template <class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << "(" << p.first << ", " << p.second << ")";
}
void dbgprint(const string &fmt) { cerr << endl; }
template <class H, class... T>
void dbgprint(const string &fmt, const H &h, const T &...r) {
  cerr << fmt.substr(0, fmt.find(",")) << "= " << h << " ";
  dbgprint(fmt.substr(fmt.find(",") + 1), r...);
}
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = (int)1e9;
const double INF = 1e12, EPS = 1e-9;

const int MX = 3000;
bool p[MX];
int n;
ll s[100010];
map<ll, int> sqs;

vector<ll> comp(const vector<ll> &m) {
  if (m.size() == 0)
    return m;
  vector<ll> res;
  rep(i, m.size()) {
    if (m[i] >= MX) {
      if (sqs.count(m[i]))
        res.pb(sqs[m[i]]);
      else
        res.pb(m[i] * m[i]);
      continue;
    }
    if (i + 1 < m.size() && m[i] == m[i + 1])
      res.pb(m[i++]);
    else {
      res.pb(m[i]);
      res.pb(m[i]);
    }
  }
  return res;
}

int main() {
  cin.tie(0);
  cin.sync_with_stdio(0);
  vi prime;
  for (int i = 2; i * i < MX; i++)
    if (!p[i])
      for (int j = i * i; j < MX; j += i)
        p[j] = 1;
  for (int i = 2; i < MX; i++)
    if (!p[i])
      prime.pb(i);
  for (ll i = 1; i * i <= 1e10; i++)
    sqs[i * i] = i;

  cin >> n;
  rep(i, n) cin >> s[i];
  map<vector<ll>, int> M;
  set<vector<ll>> done;
  int ans = 0;

  rep(ii, n) {
    ll m = s[ii];
    vector<ll> v;

    for (int i = 0; i < prime.size() && (ll)prime[i] * prime[i] <= m; i++)
      if (m % prime[i] == 0) {
        int cnt = 0;
        for (; m % prime[i] == 0; cnt++)
          m /= prime[i];
        cnt %= 3;
        rep(it, cnt) v.pb(prime[i]);
      }
    if (m > 1)
      v.pb(m);
    sort(all(v));
    M[v]++;
  }

  done.insert(vector<ll>());
  for (auto m : M) {
    if (done.count(m.first))
      continue;
    auto mm = comp(m.first);

    if (M.count(mm)) {
      int l = m.second, r = M[mm];
      ans += max(l, r);
      done.insert(mm);
    } else
      ans += m.second;
  }
  if (M.count(vector<ll>()))
    ans++;
  cout << ans << endl;
  return 0;
}