Submission #537061

#	Time	Username	Problem	Language	Result	Execution time	Memory
537061		cig32	Port Facility (JOI17_port_facility)	C++17	22 / 100	6087 ms	283656 KiB

port_facility

#include "bits/stdc++.h"
using namespace std;
const int MAXN = 2e6 + 10;
const int MOD = 1e9 + 7;
#define int long long
 
mt19937_64 rng((int)std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
  int u = uniform_int_distribution<int>(x, y)(rng); return u;
}
long long bm(long long b, long long p) { 
  if(p==0) return 1;
  long long r = bm(b, p/2);
  if(p&1) return (((r*r) % MOD) * b) % MOD;
  return (r*r) % MOD;
}
struct segment {
  int l, r;
};
bool cmp(segment a, segment b) {
  return a.l < b.l;
}
vector<int> adj[MAXN];

char c[MAXN];

bool vis[MAXN];
void dfs(int node, char cur) {
  c[node] = cur, vis[node] = 1;
  for(int x: adj[node]) {
    if(!vis[x]) {
      dfs(x, (cur == 'A' ? 'B' : 'A'));
    }
  }
}

int st[8 * MAXN];

void u(int l, int r, int tar, int idx, int val) {
  if(l == r) {
    st[idx] = val; return;
  }
  int mid = (l + r) >> 1;
  if(tar <= mid) u(l, mid, tar, 2*idx+1, val);
  else u(mid+1, r, tar, 2*idx+2, val);
  st[idx] = max(st[2*idx+1], st[2*idx+2]);
}
int qu(int l, int r, int constl, int constr, int idx) {
  if(l<=constl && constr<=r) return st[idx];
  int mid = (constl+constr) >> 1;
  if(mid<l || r<constl) return qu(l, r, mid+1, constr, 2*idx+2);
  else if(constr<l || r<mid+1) return qu(l, r, constl, mid, 2*idx+1);
  return max(qu(l, r, constl, mid, 2*idx+1), qu(l, r, mid+1, constr, 2*idx+2));
}

void update(int i, int v) {
  u(0, 2*MAXN-1, i, 0, v);
}
int query(int l, int r) {
  return qu(l, r, 0, 2*MAXN-1, 0);
}

void solve(int tc) {
  int n;
  cin >> n;
  segment s[n+1];
  for(int i=1; i<=n; i++)cin >> s[i].l >> s[i].r;
  sort(s+1, s+n+1, cmp);
  int oops[2*n + 1];
  for(int i=1; i<=n; i++) oops[s[i].r] = i;
  for(int i=1; i<=n; i++) update(s[i].l, s[i].r);
  for(int i=1; i<=n; i++) {
    if(s[i].l + 1 == s[i].r) continue;
    vector<pair<int, int> > v;
    while(1) {
      int res = query(s[i].l + 1, s[i].r - 1);
      if(res > s[i].r) {
        adj[i].push_back(oops[res]);
        adj[oops[res]].push_back(i);
        v.push_back({s[oops[res]].l, res});
        update(s[oops[res]].l, -1);
      }
      else {
        break;
      }
    }
    for(pair<int, int> x: v) {
      update(x.first, x.second);
    }
  }
  int compo = 0;
  for(int i=1; i<=n; i++) {
    if(!vis[i]) {
      compo++;
      dfs(i, 'A');
    }
  }
  for(int i=1; i<=n; i++) {
    for(int x: adj[i]) {
      if(c[i] == c[x]) {
        cout << "0\n"; return;
      }
    }
  }
  cout << bm(2, compo) << '\n';
}

int32_t main(){
  ios::sync_with_stdio(0); cin.tie(0);
  int t = 1; //cin >> t;
  for(int i=1; i<=t; i++) solve(i);
}
/*
3 3
0 1 1 3
1 2 4 1
0 2 3 1
*/

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22