Submission #747815

#	Time	Username	Problem	Language	Result	Execution time	Memory
747815		Sam_a17	Event Hopping 2 (JOI21_event2)	C++17	100 / 100	373 ms	39268 KiB

event2

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
 
#define pb push_back
#define popf pop_front
#define popb pop_back
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
 
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T> void print(T v[],T n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
 
// for random generations
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
// mt19937 myrand(131);

// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
 
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
  fastIO();
 
  if (str != "") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  }
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 1e5 + 10, LOG = 21;
int up[N][LOG];
int n, k;

// segment Tree Max
// Range Queries
struct segTree {
  vector<pair<long long, long long>> mTree;
  int size;

  void init(long long n) {
    size = 1;
    while(size < n)  {
      size *= 2;
    }
    mTree.assign(2 * size - 1, {INT64_MAX, -1});
  }

  pair<long long, long long> combine(pair<long long, long long> a, pair<long long, long long> b) {
    if(a.first < b.first) {
      return a;
    } else if(a.first > b.first) {
      return b;
    } else {
      return {a.first, min(a.second, b.second)};
    }
  }

  void upd(int u, long long v, int ind, int x, int lx, int rx) { // set value at pos u
    if(rx - lx == 1) {
      if(v < mTree[x].first) {
        mTree[x].first = v;
        mTree[x].second = ind;
      }
      return;
    }

    int m = (lx + rx) / 2;
    if(u < m) {
      upd(u, v, ind, 2 * x + 1, lx, m);
    }else {
      upd(u, v, ind, 2 * x + 2, m, rx);
    }
    mTree[x] = combine(mTree[2 * x + 1], mTree[2 * x + 2]);
  }

  void upd(int u, long long v, int ind) {
    upd(u, v, ind, 0, 0, size);
  }

  pair<long long, long long> qry (int l, int r, int x, int lx, int rx) { // range queries
    if(l >= rx || lx >= r) {
      return {INT64_MAX, -1};
    }
    if(lx >= l && r >= rx) {
      return mTree[x];
    }

    int m = (rx + lx) / 2;
    auto s1 = qry(l, r, 2 * x + 1, lx, m);
    auto s2 = qry(l, r, 2 * x + 2, m, rx);
    return combine(s1, s2);
  }

  pair<long long, long long> qry(int l, int r) {
    return qry(l, r, 0, 0, size);
  }
};

segTree seg_max;


struct segmTree {
  struct node {
      long long value, lazy;
  };
  int size = 1;
  vector<node> tree;

  void init(int s) {
    while(s > size) {
        size *= 2;
    }

    tree.assign(2 * size - 1, {0, 0});
  }

  void propagate(int x, int lx, int rx) {
    if(rx - lx == 1 || !tree[x].lazy) {
      tree[x].lazy = 0;
      return;
    }

    int mid = (lx + rx) / 2;
    tree[2 * x + 1].value += tree[x].lazy * (mid - lx);
    tree[2 * x + 1].lazy += tree[x].lazy;

    tree[2 * x + 2].value += tree[x].lazy * (rx - mid);
    tree[2 * x + 2].lazy += tree[x].lazy;

    tree[x].lazy = 0;
  }

  void upd(int l, int r, long long value, int x, int lx, int rx) {
    propagate(x, lx, rx);
    if(lx >= r || rx <= l) {
      return;
    }

    if(lx >= l && rx <= r) {
      tree[x] = {tree[x].value + value * (rx - lx), value};
      propagate(x, lx, rx);
      return;
    }

    int mid = (lx + rx) / 2;
    upd(l, r, value, 2 * x + 1, lx, mid);
    upd(l, r, value, 2 * x + 2, mid, rx);
    tree[x].value = tree[2 * x + 1].value + tree[2 * x + 2].value;
  }

  void upd(int l, int r, long long value) {
    upd(l, r, value, 0, 0, size);
  }

  long long qry(int l, int r, int x, int lx, int rx) {
    propagate(x, lx, rx);
    if(lx >= r || rx <= l) {
      return 0;
    }

    if(lx >= l && rx <= r) {
      return tree[x].value;
    }

    int mid = (lx + rx) / 2;
    long long s1 = qry(l, r, 2 * x + 1, lx, mid);
    long long s2 = qry(l, r, 2 * x + 2, mid, rx);
    return s1 + s2;
  }

  long long qry(int l, int r) {
    return qry(l, r, 0, 0, size);
  }
};

segmTree seg, del;

vector<pair<pair<int, int>, int>> a;
pair<int, int> arr[N];

int calc(int l, int r) {
  auto u = seg_max.qry(l, r + 1);
  if(u.first > r) {
    return 0;
  }


  int curr = u.second, go = 1;
  for(int i = LOG - 1; i >= 0; i--) {
    if(up[curr][i] < n) {
      int ind = up[curr][i];
      if(arr[ind].second <= r) {
        curr = up[curr][i];
        go += (1 << i);
      }
    }
  }

  return go;
}

void solve_() {
  cin >> n >> k;

  vector<int> compress;

  for(int i = 1; i <= n; i++) {
    int l, r; cin >> l >> r;
    a.push_back({{r, l}, i - 1});

    //
    compress.push_back(l);
    compress.push_back(r);
  }

  sort(all(a));
  sort(all(compress));
  uniq(compress);

  seg_max.init(sz(compress) + 4);

  for(int i = 0; i < n; i++) {
    a[i].first.first = lower_bound(all(compress), a[i].first.first) - compress.begin() + 1;
    a[i].first.second = lower_bound(all(compress), a[i].first.second) - compress.begin() + 1;
    arr[a[i].second] = {a[i].first.second, a[i].first.first};
    seg_max.upd(a[i].first.second, a[i].first.first, a[i].second);
  }

  int it = 0;
  for(int i = 0; i < n; i++) {
    while(it < n && a[it].first.second < a[i].first.first) {
      it++;
    }

    if(it == n) {
      up[a[i].second][0] = n;
    } else {
      up[a[i].second][0] = a[it].second;
    }
  }

  for(int i = 0; i < LOG; i++) {
    up[n][i] = n;
  }

  for(int j = 1; j < LOG; j++) {
    for(int i = 0; i < n; i++) {
      up[i][j] = up[up[i][j - 1]][j - 1];
    }
  }

  set<int> st;
  
  st.insert(0);
  st.insert(sz(compress) + 2);

  if(calc(0, sz(compress) + 2) < k) {
    cout << -1 << '\n';
    return;
  }
  
  seg.init(sz(compress) + 5);
  vector<int> answ;

  int all = calc(0, sz(compress) + 2);
  for(int i = 0; i < n; i++) {
    // dbg(arr[i])
    int s1 = seg.qry(arr[i].first, arr[i].second);
    if(s1) continue;

    st.insert(arr[i].first);
    st.insert(arr[i].second);

    auto itl = prev(st.find(arr[i].first));
    auto itr = next(st.find(arr[i].second));

    int new_all = all - calc(*itl, *itr);
    new_all += calc(*itl, arr[i].first) + 1 + calc(arr[i].second, *itr); 
    if(new_all >= k) {
      answ.push_back(i + 1);
      // dbg(make_pair(arr[i].first, arr[i].second))
      seg.upd(arr[i].first, arr[i].second, 1);
      all = new_all;
    } else {
      if(!seg.qry(arr[i].first, arr[i].first + 1)) st.erase(arr[i].first);
      if(!seg.qry(arr[i].second, arr[i].second + 1)) st.erase(arr[i].second);
    }

    if(sz(answ) == k) break;
  }

  assert(sz(answ) == k);
  for(auto i: answ) {
    cout << i << '\n';
  }
}
 
int main() {
  setIO();
  
  auto solve = [&](int test_case)-> void {
    while(test_case--) {
      solve_();
    }
  };
 
  int test_cases = 1; 
  // cin >> test_cases;
  solve(test_cases);
 
  return 0;
}

Compilation message (stderr)

event2.cpp: In function 'void setIO(std::string)':
event2.cpp:66:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
event2.cpp:67:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 1 / 1
• Subtask 3: 31 / 31
• Subtask 4: 61 / 61