제출 #551827

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
551827		oleh1421	Joker (BOI20_joker)	C++17	25 / 100	530 ms	21296 KiB

Joker

//#pragma GCC target("avx2")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
//#define endl '\n'
using namespace __gnu_pbds;
typedef long double ld;
//#define int ll
using namespace std;
mt19937 rnd(time(NULL));
typedef long long ll;
const int N=400100;
const int K=10000;
int a[N],b[N];
int ans[N];
int l[N/K+1];
int r[N/K+1];
int group[N];


int w[N];
int sz[N];
int dsu[N];
bool BAD=false;
vector<pair<int,pair<int,int> > >CH;
pair<int,int>get(int x){
    if (x==dsu[x]) return {x,w[x]};
    auto cur=get(dsu[x]);
    cur.second^=w[x];
    return cur;
}
void unite(int a,int b){
    if (a==0 && b==0) return;
    auto x=get(a);
    auto y=get(b);
    if (x.first==y.first){
        if (x.second==y.second){
            CH.push_back({4,{-1,BAD}});
            BAD=true;
        }
        return;
    }
    if (sz[x.first]>sz[y.first]) swap(x,y);
    CH.push_back({1,{x.first,dsu[x.first]}});
    CH.push_back({2,{y.first,sz[y.first]}});
    CH.push_back({3,{x.first,w[x.first]}});
    dsu[x.first]=y.first;
    sz[y.first]+=sz[x.first];
    w[x.first]^=(x.second^y.second^1^w[y.first]);
}
void roll_back(){
    if (!CH.empty()){
        auto cur=CH.back();
        CH.pop_back();
        if (cur.first==1) dsu[cur.second.first]=cur.second.second;
        else if (cur.first==2) sz[cur.second.first]=cur.second.second;
        else if (cur.first==3) w[cur.second.first]=cur.second.second;
        else BAD=cur.second.second;
    }
}
int L[N],R[N];
bool used[N];
int n,m,q;
void rec(int l,int r,int L,int R){
    if (l>r) return;
    int m=(l+r)/2;
    int len=CH.size();
    for (int i=l;i<=m;i++){
        unite(a[i],b[i]);
    }
    int ind=-1;
    for (int i=R;i>=L;i--){
        unite(a[i],b[i]);
        if (BAD){
            ind=i;
            break;
        }
    }
    ans[m]=ind;
    while (CH.size()>len) roll_back();
    for (int i=R;i>ind;i--){
        unite(a[i],b[i]);
    }
    rec(l,m-1,L,ind);
    while (CH.size()>len) roll_back();
    for (int i=R;i>ind;i--){
        unite(a[i],b[i]);
    }
    for (int i=l;i<=m;i++){
        unite(a[i],b[i]);
    }
    rec(m+1,r,ind,R);
}
void solve(){
    cin>>n>>m>>q;
    for (int i=1;i<=m;i++){
        cin>>a[i]>>b[i];
    }
    for (int i=1;i<=q;i++){
        cin>>L[i]>>R[i];
        used[L[i]-1]=true;
    }
    for (int i=1;i<=n;i++){
        dsu[i]=i;
        sz[i]=1;
        w[i]=0;
    }
    BAD=false;
    for (int i=1;i<=m;i++){
        unite(a[i],b[i]);
    }
    if (!BAD){
        for (int i=0;i<=m;i++) ans[i]=0;
    } else {
        while (!CH.empty()) roll_back();
        rec(0,m,1,m+1);
    }


    for (int i=1;i<=q;i++){
        if (ans[L[i]-1]<=R[i]) cout<<"NO\n";
        else cout<<"YES\n";
    }



}

int32_t main() {

    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int tt=1;
    while (tt--){
        solve();
    }

    return 0;
}

/**
6 8 2
1 3
1 5
1 6
2 5
2 6
3 4
3 5
5 6
4 8
4 7
**/

컴파일 시 표준 에러 (stderr) 메시지

Joker.cpp: In function 'void rec(int, int, int, int)':
Joker.cpp:79:21: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   79 |     while (CH.size()>len) roll_back();
      |            ~~~~~~~~~^~~~
Joker.cpp:84:21: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   84 |     while (CH.size()>len) roll_back();
      |            ~~~~~~~~~^~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 8
• Subtask 3: 25 / 25
• Subtask 4: 0 / 10
• Subtask 5: 0 / 22
• Subtask 6: 0 / 29