Submission #166933

#	Time	Username	Problem	Language	Result	Execution time	Memory
166933		theStaticMind	Port Facility (JOI17_port_facility)	C++14	22 / 100	6056 ms	42600 KiB

port_facility

#include<bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define ii pair<int,int>
#define all(x) (x).begin(),(x).end()
#define INF 100000000000000000
#define modulo 1000000007
#define mod 998244353
#define int long long int
using namespace std;
vector<int>no(1000004);
vector<int>vis(1000004,0);
vector<int>lazy(1000004,0);
vector<int>sz(1000004,1);
vector<pair<int,ii>> arr;
int F(int x){
      while(x!=no[x]){
            x=no[x];
      }
      return x;
}
int get_lazy(int x){
      int l=lazy[x];
      while(x!=no[x]){
            x=no[x];
            l^=lazy[x];
      }
      return l;
}
bool merge(int x,int y){
      int X=F(x);
      int Y=F(y);
      if(X==Y){
            if(vis[x]^get_lazy(x)==vis[y]^get_lazy(y))return false;
      }
      else{
            if(sz[X]<sz[Y]){
                  swap(X,Y);
                  swap(x,y);
            }
            if(vis[x]^get_lazy(x)==vis[y]^get_lazy(y)){
                  lazy[Y]^=1;
            }
            no[Y]=X;
            sz[X]+=sz[Y];
      }
      return true;
}
int32_t main(){
      ios_base::sync_with_stdio(false);
      cin.tie(NULL);
   //   freopen("q.gir","r",stdin);
   //   freopen("q.cik","w",stdout);
      int n,ans=1;
      for(int i=0;i<no.size();i++)no[i]=i;
      cin>>n;
      for(int i=1;i<=n;i++){
            int a,b;
            cin>>a>>b;
            arr.pb({a,{b,i}});
            arr.pb({b,{b,-i}});
      }
      sort(all(arr));
      set<ii>data;
      for(int i=0;i<arr.size();i++){
            int x=arr[i].first,y=arr[i].second.first,id=arr[i].second.second;
            if(id<0){
                  data.erase({x,-id});
            }
            else{
                  for(set<ii>::iterator itr=data.lower_bound({x,0});itr!=data.end()&&itr->first<y;itr++){
                        if(!merge(itr->second,id)){
                              cout<<0;
                              return 0;
                        }
                  }
                  data.insert({y,id});
            }
      }
      for(int i=1;i<=n;i++){
            if(F(i)==i)ans=ans*2%modulo;
      }
      cout<<ans;
}

Compilation message (stderr)

port_facility.cpp: In function 'bool merge(long long int, long long int)':
port_facility.cpp:34:34: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
             if(vis[x]^get_lazy(x)==vis[y]^get_lazy(y))return false;
port_facility.cpp:41:34: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
             if(vis[x]^get_lazy(x)==vis[y]^get_lazy(y)){
port_facility.cpp: In function 'int32_t main()':
port_facility.cpp:55:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       for(int i=0;i<no.size();i++)no[i]=i;
                   ~^~~~~~~~~~
port_facility.cpp:65:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
       for(int i=0;i<arr.size();i++){
                   ~^~~~~~~~~~~

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