Submission #684550

#	Time	Username	Problem	Language	Result	Execution time	Memory
684550		urosk	Joker (BOI20_joker)	C++14	0 / 100	1 ms	340 KiB

Joker

#define here cerr<<"===========================================\n"
#define dbg(x) cerr<<#x<<": "<<x<<endl;
#include "bits/stdc++.h"
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
#define ld double
#define ll long long
#define llinf 100000000000000000LL // 10^17
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) (ll)(a.size())
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {cerr<<#a<<": ";for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
#define cer(a) {cerr<<#a<<": ";for(ll x_ : a) cerr<<x_<< " ";cerr<<endl;}

#define daj_mi_malo_vremena ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);

using namespace std;
//using namespace __gnu_pbds;
/*
ll add(ll x,ll y){
    x+=y;
    if(x<0){
        x%=mod;
        x+=mod;
    }else{
        if(x>=mod) x%=mod;
    }
    return x;
}
ll mul(ll a,ll b){
	ll ans = (a*b)%mod;
	if(ans<0) ans+=mod;
	return ans;
}
typedef tree<int,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef tree<int,null_type,less_equal<ll>,rb_tree_tag,tree_order_statistics_node_update> ordered_multiset;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll rnd(ll l,ll r){
    return uniform_int_distribution<ll>(l,r)(rng);
}
*/
#define maxn 200005
ll n,m,q;
pll e[maxn];
ll dsu[maxn],sizi[maxn];
ll last[maxn];
ll root(ll x){
    while(x!=dsu[x]) x = dsu[x];
    return x;
}
ll col(ll x){
    ll cnt = 0;
    while(x!=dsu[x]){cnt++;x = dsu[x];}
    return cnt&1;
}
stack<pll> st;
ll cnt = 0;
void upd(ll u,ll v){
    u = root(u);
    v = root(v);
    if(sizi[u]>sizi[v]) swap(u,v);
    if(u==v){
        if(col(u)==col(v)) cnt++;
    }else{
        sizi[u]+=sizi[v];
        dsu[v] = u;
    }
    st.push({v,u});
}
void roll(){
    if(st.empty()) here;
    ll v = st.top().fi;
    ll u = st.top().sc;
    if(dsu[v]==u){
        st.pop();
        sizi[u]-=sizi[v];
        dsu[v] = v;
    }else{
        if(col(u)==col(v)) cnt--;
    }
}
void reshi(ll l,ll r,ll tl,ll tr){
    if(l>r) return;
    ll mid = (l+r)/2;
    for(ll i = l;i<mid;i++){
        upd(e[i].fi,e[i].sc);
    }
    ll i = tr;
    if(cnt) last[mid] = m+1;
    while(!cnt&&i>=max(mid+1,tl)){
        upd(e[i].fi,e[i].sc);
        i--;
    }
    for(ll j = i+2;j<=tr;j++) roll();
    if(!last[mid]) last[mid] = i;
    //cerr<<cnt<< " "<<l<< " "<<r<< " "<<tl<< " "<<tr<<" "<<i<<endl;
    reshi(mid+1,r,max(mid+1,i),tr);
    for(ll j = l;j<mid;j++) roll();
    for(ll j = i+1;j<=tr;j++) upd(e[j].fi,e[j].sc);
    reshi(l,mid-1,tl,i);
}
void tc(){
    cin >> n >> m >> q;
    for(ll i = 1;i<=m;i++) cin >> e[i].fi >> e[i].sc;
    iota(dsu+1,dsu+1+n,1);
    reshi(1,m,1,m);
    //ceri(last,1,n);
    while(q--){
        ll l,r; cin >> l >> r;
        if(last[l]>=r) cout<<"YES"<<endl;
        else cout<<"NO"<<endl;
    }
}
int main(){
	daj_mi_malo_vremena
    int t; t = 1;
    while(t--){
        tc();
    }
	return 0;
}

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