Submission #296308

#	Time	Username	Problem	Language	Result	Execution time	Memory
296308		BThero	Long Mansion (JOI17_long_mansion)	C++17	100 / 100	1572 ms	121636 KiB

long_mansion

// chrono::system_clock::now().time_since_epoch().count()
#include<bits/stdc++.h>

#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define debug(x) cerr << #x << " = " << x << endl;

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int MAXN = (int)5e5 + 5;

vector<int> group[MAXN];
vector<int> keys[MAXN];
int betw[MAXN];
int A[MAXN], B[MAXN];
int L[MAXN], R[MAXN];
int n, q;

void calcB() {
  B[0] = n + 1;
  
  for (int i = 1; i <= n; ++i) {
    group[i].clear();
    B[i] = n + 1;
  }
  
  for (int i = 2; i <= n; ++i) {
    group[betw[i - 1]].pb(i - 1);
    
    for (int x : keys[i]) {
      for (int y : group[x]) {
        B[y] = i;
      }
      
      group[x].clear();
    }
  }
}

void calcA() {
  A[n + 1] = 0;
  
  for (int i = 1; i <= n; ++i) {
    group[i].clear();
    A[i] = 0;
  }
  
  for (int i = n - 1; i > 0; --i) {
    group[betw[i]].pb(i + 1);
    
    for (int x : keys[i]) {
      for (int y : group[x]) {
        A[y] = i;
      }
      
      group[x].clear();
    }
  }
}

void calcR() {
  for (int i = 1; i <= n; ++i) {
    R[i] = n + 1;
  }
  
  for (int i = 0; i <= n + 1; ++i) {
    group[i].clear();
  }
  
  for (int i = 1; i <= n; ++i) {
    group[B[i - 1]].pb(i);
  }
  
  set<int> S, T;
  
  for (int i = 1; i <= n + 1; ++i) {
    S.insert(i);
    T.insert(i);
  }
  
  for (int r = 1; r <= n; ++r) {
    for (int x : group[r]) {
      S.erase(x);
    }
  
    // A[r + 1] < l
    int l = A[r + 1] + 1;
    l = *S.lower_bound(l);
    // B[l - 1] > r
    
    auto it = T.lower_bound(l);
    
    while (*it <= r) {
      R[*it] = r;
      it = T.erase(it);
    }
  }
}

void calcL() {
  for (int i = 1; i <= n; ++i) {
    L[i] = 0;
  }
  
  for (int i = 0; i <= n + 1; ++i) {
    group[i].clear();
  }
  
  for (int i = 1; i <= n; ++i) {
    group[A[i + 1]].pb(i);
  }
  
  set<int> S, T;
  
  for (int i = 0; i <= n + 1; ++i) {
    S.insert(i);
    T.insert(i);
  }
  
  for (int l = n; l > 0; --l) {
    for (int x : group[l]) {
      S.erase(x);
    }
  
    // B[l - 1] > r
    int r = B[l - 1] - 1;
    r = *(--S.upper_bound(r));
    // A[r + 1] < l
    auto it = T.lower_bound(l);
    
    while (*it <= r) {
      L[*it] = l;
      it = T.erase(it);
    }
  }
}

void solve() {
  scanf("%d", &n);
  
  for (int i = 1; i < n; ++i) {
    scanf("%d", &betw[i]);
  }
  
  for (int i = 1; i <= n; ++i) {
    int sz;
    scanf("%d", &sz);
    keys[i].resize(sz);
    
    for (int j = 0; j < sz; ++j) {
      scanf("%d", &keys[i][j]);
    }
  }
  
  calcB();
  calcA();
  calcR();
  calcL();
  
  scanf("%d", &q);
  
  for (int i = 1; i <= q; ++i) {
    int a, b;
    scanf("%d %d", &a, &b);
    // a -> b
    bool ans = 1;
    
    if (a < b) {
      if (R[a] < b) {
        ans = 0;
      }
    }
    else {
      if (L[a] > b) {
        ans = 0;
      }
    }
    
    if (ans) {
      printf("YES\n");
    }
    else {
      printf("NO\n");
    }
  }
}

int main() {
  int tt = 1;
  
  while (tt--) {
    solve();
  }

  return 0;
}

Compilation message (stderr)

long_mansion.cpp: In function 'void solve()':
long_mansion.cpp:146:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  146 |   scanf("%d", &n);
      |   ~~~~~^~~~~~~~~~
long_mansion.cpp:149:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  149 |     scanf("%d", &betw[i]);
      |     ~~~~~^~~~~~~~~~~~~~~~
long_mansion.cpp:154:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  154 |     scanf("%d", &sz);
      |     ~~~~~^~~~~~~~~~~
long_mansion.cpp:158:12: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  158 |       scanf("%d", &keys[i][j]);
      |       ~~~~~^~~~~~~~~~~~~~~~~~~
long_mansion.cpp:167:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  167 |   scanf("%d", &q);
      |   ~~~~~^~~~~~~~~~
long_mansion.cpp:171:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  171 |     scanf("%d %d", &a, &b);
      |     ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 15 / 15
• Subtask 4: 75 / 75