Submission #566627

#	Time	Username	Problem	Language	Result	Execution time	Memory
566627		zaneyu	Regions (IOI09_regions)	C++14	100 / 100	5332 ms	47376 KiB

regions

/*input
6 3 4
1
1 2
1 3
2 3
2 3
5 1
1 2
1 3
2 3
3 1
*/
#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<long long,null_type,less_equal<long long>,rb_tree_tag,tree_order_statistics_node_update> indexed_set;
#pragma GCC optimize("Ofast")
//#pragma GCC target("avx2")
//order_of_key #of elements less than x
// find_by_order kth element
using ll=long long;
using ld=long double;
using pii=pair<int,int>;
#define f first
#define s second
#define pb push_back
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define FILL(n,x) memset(n,x,sizeof(n))
#define ALL(_a) _a.begin(),_a.end()
#define sz(x) (int)x.size()
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()),c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
const ll maxn=2e5+5;
const ll maxlg=__lg(maxn)+2;
const ll INF64=4e18;
const int INF=0x3f3f3f3f;
const ll MOD=1e9+7;
const ld PI=acos(-1);
const ld eps=1e-6;
#define lowb(x) x&(-x)
#define MNTO(x,y) x=min(x,(__typeof__(x))y)
#define MXTO(x,y) x=max(x,(__typeof__(x))y)
template<typename T1,typename T2>
ostream& operator<<(ostream& out,pair<T1,T2> P){
    out<<P.f<<' '<<P.s;
    return out;
}
template<typename T>
ostream& operator<<(ostream& out,vector<T> V){
    REP(i,sz(V)) out<<V[i]<<((i!=sz(V)-1)?"\n":"");
    return out;
}
ll mult(ll a,ll b){
    return a*b%MOD;
}
ll mypow(ll a,ll b){
    a%=MOD;
    if(a==0) return 0;
    if(b<=0) return 1;
    ll res=1LL;
    while(b){
        if(b&1) res=(res*a)%MOD;
        a=(a*a)%MOD;
        b>>=1;
    }
    return res;
}
vector<int> v[maxn];
vector<int> vv[maxn],v2[maxn];
int bs;
int arr[maxn];
ll save[25000][405];
ll save2[405][25000];
int big[maxn];
int cntt[maxn];
void dfs(int u,vector<int> &cnt){
    if(big[arr[u]]!=-1) cnt[big[arr[u]]]++,cntt[big[arr[u]]]++;
    for(int x:v[u]){
        vector<int> asd(bs);
        dfs(x,asd);
        REP(j,bs) cnt[j]+=asd[j];
    }
    REP(j,bs) save[arr[u]][j]+=cnt[j];
    REP(j,bs) save2[j][arr[u]]+=cntt[j];
    if(big[arr[u]]) cntt[big[arr[u]]]--;
}
int in[maxn],out[maxn];
int cur=0;
void dfs2(int u){
    in[u]=cur++;
    for(int x:v[u]) dfs2(x);
    out[u]=cur-1;
}
const int blk=500;
int main(){
    int n,r,q;
    cin>>n>>r>>q;
    REP(i,n){
        int p,x;
        if(i) cin>>p,--p,v[p].pb(i);
        cin>>x;
        --x;
        arr[i]=x;
    }
    int bs=0;
    REP(i,n){
        if(sz(v[i])>=blk){
            big[i]=bs++;
        }
        else big[i]=-1;
    }    
    vector<int> cnt(bs);
    dfs(0,cnt);
    dfs2(0);
    REP(i,n) vv[arr[i]].pb(in[i]),v2[arr[i]].pb(out[i]);
    REP(i,r) sort(ALL(vv[i])),sort(ALL(v2[i]));
    while(q--){
        int a,b;
        cin>>a>>b;
        --a,--b;
        if(big[a]!=-1){
            cout<<save2[big[a]][b]<<endl;
            continue;
        }
        if(big[b]!=-1){
            cout<<save[a][big[b]]<<endl;
            continue;
        }
        int l=0,r=0;
        int ans=0;
        for(int x:v2[a]){
            while(r<sz(vv[b]) and vv[b][r]<=x) ++r;
            ans+=r;
        }
        for(int x:vv[a]){
            while(l<sz(vv[b]) and vv[b][l]<x) ++l;
            ans-=l;
        }
        cout<<ans<<endl;
    }
} 

• Subtask 1: 15 / 15
• Subtask 2: 85 / 85