제출 #598016

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
598016		slime	Stranded Far From Home (BOI22_island)	C++14	100 / 100	591 ms	126684 KiB

island

#include "bits/stdc++.h"
using namespace std;
#define int long long
const int MAXN = 3e5 + 10;
const int MOD = 1e9 + 7;
#define ll __int128
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;
}
ll read() { int x; cin >> x; return (ll)x; }
long long bm(long long b, long long p) {
  if(p==0) return 1 % MOD;
  long long r = bm(b, p >> 1);
  if(p&1) return (((r*r) % MOD) * b) % MOD;
  return (r*r) % MOD;
}
long long inv(long long b) { 
  return bm(b, MOD-2);
}
long long f[MAXN];
long long nCr(int n, int r) { 
  long long ans = f[n]; ans *= inv(f[r]); ans %= MOD;
  ans *= inv(f[n-r]); ans %= MOD; return ans;
}
long long fib[MAXN], lucas[MAXN];
void precomp() { 
  for(int i=0; i<MAXN; i++) f[i] = (i == 0 ? 1 % MOD : (f[i-1] * i) % MOD); 
  lucas[0] = 2;
  lucas[1] = 1;
  for(int i=2; i<MAXN; i++) lucas[i] = (lucas[i-2] + lucas[i-1]) % MOD;
  fib[0] = 0;
  fib[1] = 1;
  for(int i=2; i<MAXN; i++) fib[i] = (fib[i-2] + fib[i-1]) % MOD;
}
int fastlog(int x) {
  return (x == 0 ? -1 : 64 - __builtin_clzll(x) - 1);
}
void gay(int i) { cout << "Case #" << i << ": "; }
int csb(int l, int r, int k) { // count number of [l, r] such that i & 2^k > 0
  if(l > r) return 0;
  if(l == 0) {
    int s = r / (1ll << (k+1)); // number of complete cycles
    int t = r % (1ll << (k+1));
    int ans = s * (1ll << k);
    ans += (t >= (1ll << k) ? t - (1ll << k) + 1 : 0);
    return ans;
  }
  else return csb(0, r, k) - csb(0, l - 1, k);
}
int lis(vector<int> a) {
  int n = a.size();
  int bucket[n+1];
  for(int i=1; i<=n; i++) bucket[i] = 1e18;
  int ans = 1;
  for(int x: a) {
    auto it = lower_bound(bucket + 1, bucket +n +1, x);
    int d = distance(bucket, it);
    ans = max(ans, d);
    bucket[d] = min(bucket[d], x);
  }
  return ans;
}
struct disjoint_sets {
  vector<int> dsu;
  vector<int> sizes;
  public:
  void resize(int n) {
    dsu.resize(n + 10);
    sizes.resize(n + 10);
    for(int i=0; i<n+10; i++) dsu[i] = i;
  }
  void set_size(int i, int x) {
    sizes[i] = x;
  }
  int get_size(int i) {
    return sizes[set_of(i)];
  }
  int set_of(int u) {
    if(dsu[u] == u) return u;
    return dsu[u] = set_of(dsu[u]);
  }
  void union_sets(int u, int v) {
    int o = sizes[set_of(u)] + sizes[set_of(v)];
    dsu[set_of(u)] = set_of(v);
    sizes[set_of(u)] = o;
  }
};
 
void solve(int tc) {
  int n, m;
  cin >> n >> m;
  disjoint_sets dsu;
  dsu.resize(n);
  pair<int, int> s[n+1];
  for(int i=1; i<=n; i++) {
    cin >> s[i].first;
    s[i].second = i;
    dsu.set_size(i, s[i].first);
 
  }
  vector<int >adj[n+1];
  for(int i=1; i<=m; i++) {
    int a, b; cin >> a >> b;
    adj[a].push_back(b);
    adj[b].push_back(a);
  }
  sort(s+1, s+n+1);
  bool done[n+1], bad[n+1];
  for(int i=1; i<=n; i++) done[i] = 0, bad[i] = 0;


  set<int> indices[n+1];
  int rep[n+1];
  for(int i=1; i<=n; i++) {
    rep[i] = i;
    indices[i].insert(i);
  }
  for(int i=1; i<=n; i++) {
    int node = s[i].second, val = s[i].first;
    //cout << val << " " << node << " o\n";
    for(int x: adj[node]) {
      if(dsu.set_of(node) != dsu.set_of(x) && done[x]) {
        //cout << "dsu size (" << x << ") = " << dsu.get_size(x) << ", val = " << val << "\n";
        if(dsu.get_size(x) < val) {
          for(int j: indices[rep[dsu.set_of(x)]]) {
            bad[j] = 1;
          }
        }
        int nw;
        if(indices[rep[dsu.set_of(node)]].size() < indices[rep[dsu.set_of(x)]].size()) {
          nw = rep[dsu.set_of(x)];
          for(int y: indices[rep[dsu.set_of(node)]]) {
            indices[rep[dsu.set_of(x)]].insert(y);
          }
        }
        else {
          nw = rep[dsu.set_of(node)];
          for(int y: indices[rep[dsu.set_of(x)]]) {
            indices[rep[dsu.set_of(node)]].insert(y);
          }
        }

        dsu.union_sets(node, x);
        rep[dsu.set_of(node)] = nw;
        //cout << "union " << node << " " << x << "\n";
      }
    }
    done[node] = 1;
  }
  for(int i=1; i<=n; i++) cout << (bad[i] ? 0 : 1);
  cout << "\n";
}
 
/*
Set is bad if:
Sum(Set) < Min(Outgoing S)
 
If set bad, answer = 0 for all in set
Use KRT to update
 
4 3
5 7 3 5
1 2
2 3
3 4
*/
int32_t main() {
  precomp();
  ios::sync_with_stdio(0); cin.tie(0);
  int t = 1; //cin >> t;
  for(int i=1; i<=t; i++) solve(i);
}
// I don't know geometry.
// Teaming is unfair.

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 30 / 30
• Subtask 5: 35 / 35