Submission #1348849

#TimeUsernameProblemLanguageResultExecution timeMemory
1348849vneduJoker (BOI20_joker)C++17
0 / 100
36 ms5844 KiB
#include<bits/stdc++.h>
using namespace std;
#define rep(i,x,y) for(int i=(x);i<=(y);++i)
template<class T> bool maximize(T &a, const T &b){ return (a < b) ? a = b, 1 : 0; }
template<class T> bool minimize(T &a, const T &b){ return (a > b) ? a = b, 1 : 0; }
typedef long long ll;
#define all(x) x.begin(),x.end()
#define ii pair<int,int>
#define fi first
#define se second
#define pb push_back
/// end of template ///

const int N = 2e5 + 5;
const int M = 2e5 + 5;
const int Q = 2e5 + 5;
struct Dsu
{
    int n,par[N];
    bool ok,xr[N];
    Dsu() {}
    void init(int _n)
    {
        n=_n;
        for(int i=1;i<=n;++i) par[i]=i,xr[i]=0;
        ok=1;
    }
    int get(int x)
    {
        if(x==par[x]) return x;
        int p=par[x];
        par[x]=get(p);
        xr[x]^=xr[p];
        return par[x];
    }
    bool unite(int u, int v)
    {
        int s=get(u),t=get(v);
        if(s==t)
        {
            if(xr[u]==xr[v]) ok=0;
            return 0;
        }
        xr[s]=(xr[u]^1^xr[v]);
        par[s]=t;
        return 1;
    }
} dsu;
int n,m,q,U[2*M],V[2*M],f[2*M];
void dnc(int l, int r, int lo, int hi)
{
    if(l>r) return;
    int mid((l+r)>>1);
    rep(i,max(mid,lo),hi)
    {
//        cout<<mid<<' '<<i<<' '<<U[i]<<' '<<V[i]<<'\n';
        dsu.unite(U[i],V[i]);
        if(dsu.ok==0)
        {
            break;
        }
        f[mid]=i;
    }
    dsu.ok=1;
    rep(i,max(mid,lo),min(f[mid+1],2*m))
    {
        dsu.xr[U[i]]=0;
        dsu.par[U[i]]=U[i];
        dsu.xr[V[i]]=0;
        dsu.par[V[i]]=V[i];
    }
    dnc(l,mid-1,lo,f[mid]);
    dnc(mid+1,r,f[mid],hi);
}
void solve()
{
    cin>>n>>m>>q;
    rep(i,1,m) cin>>U[i]>>V[i],U[i+m]=U[i],V[i+m]=V[i];
    dsu.init(n);
    dnc(1,2*m,1,2*m);
//    rep(i,1,m) cout<<i<<' '<<f[i]<<'\n';
    rep(i,1,q)
    {
        int l,r;
        cin>>l>>r;
        int old=l;
        l=r+1;
        r=old-1+m;
        cout<<(f[l]<r?"YES\n":"NO\n");
    }
}
int main()  {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    #define TASK "OLP304"
//    freopen(TASK".inp","r",stdin);
//    freopen(TASK".out","w",stdout);

    int testcase=1;
//    cin>>testcase;

    while (testcase--)
        solve();

    return 0;
}
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...