Problem p02648 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using Pi = pair<int, int>;
using Pl = pair<ll, ll>;
using vint = vector<int>;
using vvint = vector<vint>;
using vvvint = vector<vvint>;
using vdouble = vector<double>;
using vvdouble = vector<vdouble>;
using vvvdouble = vector<vvdouble>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using uint = unsigned int;
using ull = unsigned long long;

template <typename T> using uset = unordered_set<T>;
template <typename T1, typename T2> using umap = unordered_map<T1, T2>;

constexpr int INF = (1 << 30) - 1;
constexpr ll LLINF = 1LL << 60;
constexpr int dy[] = {1, 0, -1, 0, 1, -1, -1, 1};
constexpr int dx[] = {0, 1, 0, -1, 1, 1, -1, -1};
constexpr char el = '\\n';
constexpr int mod = 1000000007;
constexpr int mod2 = 998244353;
template <typename T> T gcd(T a, T b) { return (b ? gcd(b, a % b) : a); }
template <typename T> T lcm(T a, T b) { return (a / gcd(a, b) * b); }
template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  return (a > b && (a = b, true));
}
template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  return (a < b && (a = b, true));
}
template <typename T> bool isin(T y, T x, T h, T w) {
  return (0 <= y && 0 <= x && y < h && x < w);
}
template <typename T> bool isin1(T y, T x, T h, T w) {
  return (0 < y && 0 < x && y <= h && x <= w);
}

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

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &u : v)
    is >> u;
  return (is);
}

template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  return (is >> p.first >> p.second);
}

int N;
vint V, W;
vector<vector<Pi>> A(1024);

int half(int u, int L) {
  vint v, w;
  int k = u;
  while (k > 0) {
    v.push_back(V[k]);
    w.push_back(W[k]);
    k >>= 1;
  }
  int n = v.size();
  vector<Pi> A;
  int hal = n / 2;
  // cout << " " << v << endl;
  // cout << " " << w << endl;

  for (int b = 0; b < (1 << hal); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < hal; i++) {
      if ((b >> i) & 1) {
        vsum += v[i];
        wsum += w[i];
      }
    }
    if (wsum <= L)
      A.emplace_back(wsum, -vsum);
  }
  sort(begin(A), end(A));

  vector<Pi> B;
  for (int b = 0; b < (1 << (n - hal)); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < n - hal; i++) {
      if ((b >> i) & 1) {
        vsum += v[i + hal];
        wsum += w[i + hal];
      }
    }
    if (wsum <= L)
      B.emplace_back(wsum, -vsum);
  }
  sort(begin(B), end(B));

  for (int i = 0; i < A.size(); i++) {
    A[i].second = -A[i].second;
    if (i > 0)
      chmax(A[i].second, A[i - 1].second);
    // cout << A[i].first << " " << A[i].second << "  ";
  }
  // cout << endl;

  for (int i = 0; i < B.size(); i++) {
    B[i].second = -B[i].second;
    if (i > 0)
      chmax(B[i].second, B[i - 1].second);
    // cout << B[i].first << " " << B[i].second << "  ";
  }

  int j = (int)B.size() - 1;
  int maxv = 0;
  for (int i = 0; i < A.size(); i++) {
    int vs = A[i].second, ws = A[i].first;
    while (j >= 0 && ws + B[j].first > L)
      j--;
    if (j >= 0) {
      chmax(maxv, vs + B[j].second);
    }
  }
  return (maxv);
}

int half2(int u, int L) {
  vint v, w;
  int k = u;
  while (k >= 1024) {
    v.push_back(V[k]);
    w.push_back(W[k]);
    k >>= 1;
  }
  int vv = k;

  int n = v.size();

  vector<Pi> B;
  for (int b = 0; b < (1 << n); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < n; i++) {
      if ((b >> i) & 1) {
        vsum += v[i];
        wsum += w[i];
      }
    }
    if (wsum <= L)
      B.emplace_back(wsum, vsum);
  }

  int maxv = 0;
  for (int i = 0; i < B.size(); i++) {
    int vs = B[i].second, ws = B[i].first;
    auto pos = upper_bound(begin(A[vv]), end(A[vv]), Pi(L - ws, INF)) - 1 -
               begin(A[vv]);
    chmax(maxv, A[vv][pos].second + vs);
  }
  return (maxv);
}

void Main() {
  cin >> N;
  V = vint(N + 1), W = vint(N + 1);
  for (int i = 1; i <= N; i++) {
    cin >> V[i] >> W[i];
  }

  for (int u = 512; u < 1024; u++) {
    vint v, w;
    int k = u;
    while (k > 0) {
      v.push_back(V[k]);
      w.push_back(W[k]);
      k >>= 1;
    }
    int n = v.size();

    for (int b = 0; b < 1024; b++) {
      int vsum = 0, wsum = 0;
      for (int i = 0; i < n; i++) {
        if ((b >> i) & 1) {
          vsum += v[i];
          wsum += w[i];
        }
      }
      A[u].emplace_back(wsum, -vsum);
    }
    sort(begin(A[u]), end(A[u]));

    for (int i = 0; i < A.size(); i++) {
      A[u][i].second = -A[u][i].second;
      if (i > 0)
        chmax(A[u][i].second, A[u][i - 1].second);
    }
  }

  int Q;
  cin >> Q;
  while (Q--) {
    int u, L;
    cin >> u >> L;
    if (u < 1024)
      cout << half(u, L) << el;
    else
      cout << half2(u, L) << el;
  }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  Main();
  return (0);
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using Pi = pair<int, int>;
using Pl = pair<ll, ll>;
using vint = vector<int>;
using vvint = vector<vint>;
using vvvint = vector<vvint>;
using vdouble = vector<double>;
using vvdouble = vector<vdouble>;
using vvvdouble = vector<vvdouble>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using uint = unsigned int;
using ull = unsigned long long;

template <typename T> using uset = unordered_set<T>;
template <typename T1, typename T2> using umap = unordered_map<T1, T2>;

constexpr int INF = (1 << 30) - 1;
constexpr ll LLINF = 1LL << 60;
constexpr int dy[] = {1, 0, -1, 0, 1, -1, -1, 1};
constexpr int dx[] = {0, 1, 0, -1, 1, 1, -1, -1};
constexpr char el = '\\n';
constexpr int mod = 1000000007;
constexpr int mod2 = 998244353;
template <typename T> T gcd(T a, T b) { return (b ? gcd(b, a % b) : a); }
template <typename T> T lcm(T a, T b) { return (a / gcd(a, b) * b); }
template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  return (a > b && (a = b, true));
}
template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  return (a < b && (a = b, true));
}
template <typename T> bool isin(T y, T x, T h, T w) {
  return (0 <= y && 0 <= x && y < h && x < w);
}
template <typename T> bool isin1(T y, T x, T h, T w) {
  return (0 < y && 0 < x && y <= h && x <= w);
}

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

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (auto &u : v)
    is >> u;
  return (is);
}

template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  return (is >> p.first >> p.second);
}

int N;
vint V, W;
vector<vector<Pi>> A(512);

int half(int u, int L) {
  vint v, w;
  int k = u;
  while (k > 0) {
    v.push_back(V[k]);
    w.push_back(W[k]);
    k >>= 1;
  }
  int n = v.size();
  vector<Pi> A;
  int hal = n / 2;
  // cout << " " << v << endl;
  // cout << " " << w << endl;

  for (int b = 0; b < (1 << hal); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < hal; i++) {
      if ((b >> i) & 1) {
        vsum += v[i];
        wsum += w[i];
      }
    }
    if (wsum <= L)
      A.emplace_back(wsum, -vsum);
  }
  sort(begin(A), end(A));

  vector<Pi> B;
  for (int b = 0; b < (1 << (n - hal)); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < n - hal; i++) {
      if ((b >> i) & 1) {
        vsum += v[i + hal];
        wsum += w[i + hal];
      }
    }
    if (wsum <= L)
      B.emplace_back(wsum, -vsum);
  }
  sort(begin(B), end(B));

  for (int i = 0; i < A.size(); i++) {
    A[i].second = -A[i].second;
    if (i > 0)
      chmax(A[i].second, A[i - 1].second);
    // cout << A[i].first << " " << A[i].second << "  ";
  }
  // cout << endl;

  for (int i = 0; i < B.size(); i++) {
    B[i].second = -B[i].second;
    if (i > 0)
      chmax(B[i].second, B[i - 1].second);
    // cout << B[i].first << " " << B[i].second << "  ";
  }

  int j = (int)B.size() - 1;
  int maxv = 0;
  for (int i = 0; i < A.size(); i++) {
    int vs = A[i].second, ws = A[i].first;
    while (j >= 0 && ws + B[j].first > L)
      j--;
    if (j >= 0) {
      chmax(maxv, vs + B[j].second);
    }
  }
  return (maxv);
}

int half2(int u, int L) {
  vint v, w;
  int k = u;
  while (k >= 512) {
    v.push_back(V[k]);
    w.push_back(W[k]);
    k >>= 1;
  }
  int vv = k;

  int n = v.size();

  vector<Pi> B;
  for (int b = 0; b < (1 << n); b++) {
    int vsum = 0, wsum = 0;
    for (int i = 0; i < n; i++) {
      if ((b >> i) & 1) {
        vsum += v[i];
        wsum += w[i];
      }
    }
    if (wsum <= L)
      B.emplace_back(wsum, vsum);
  }

  int maxv = 0;
  for (int i = 0; i < B.size(); i++) {
    int vs = B[i].second, ws = B[i].first;
    auto pos = upper_bound(begin(A[vv]), end(A[vv]), Pi(L - ws, INF)) - 1 -
               begin(A[vv]);
    chmax(maxv, A[vv][pos].second + vs);
  }
  return (maxv);
}

void Main() {
  cin >> N;
  V = vint(N + 1), W = vint(N + 1);
  for (int i = 1; i <= N; i++) {
    cin >> V[i] >> W[i];
  }

  for (int u = 256; u < 512; u++) {
    vint v, w;
    int k = u;
    while (k > 0) {
      v.push_back(V[k]);
      w.push_back(W[k]);
      k >>= 1;
    }
    int n = v.size();

    for (int b = 0; b < 512; b++) {
      int vsum = 0, wsum = 0;
      for (int i = 0; i < n; i++) {
        if ((b >> i) & 1) {
          vsum += v[i];
          wsum += w[i];
        }
      }
      A[u].emplace_back(wsum, -vsum);
    }
    sort(begin(A[u]), end(A[u]));

    for (int i = 0; i < A.size(); i++) {
      A[u][i].second = -A[u][i].second;
      if (i > 0)
        chmax(A[u][i].second, A[u][i - 1].second);
    }
  }

  int Q;
  cin >> Q;
  while (Q--) {
    int u, L;
    cin >> u >> L;
    if (u < 512)
      cout << half(u, L) << el;
    else
      cout << half2(u, L) << el;
  }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  Main();
  return (0);
}