Submission #799627

#	Time	Username	Problem	Language	Result	Execution time	Memory
799627		I_Love_EliskaM_	Regions (IOI09_regions)	C++14	100 / 100	6857 ms	105168 KiB

regions

#include <bits/stdc++.h>
using namespace std;

//#define int long long
#define forn(i,n) for(int i=0;i<n;++i)
#define pi pair<int,int>
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
#define vii(a,n) vector<int>a(n);forn(i,n)cin>>a[i];

const int inf=1e18;

const int K=375;
const int N=2e5+55;
const int M=25555;

int L[N],R[N];
int dp1[N/K][M];

const int sz=1<<18;
struct sgt {
	sgt *L, *R;
	int s;
	sgt() {
		L=R=NULL; s=0;
	}
	void add(int l, int r, int i) {
		s++;
		if (r-l==1) return;
		int m=(l+r)>>1;
		if (i<m) {
			if (!L) L=new sgt();
			L->add(l,m,i);
		} else {
			if (!R) R=new sgt();
			R->add(m,r,i);
		}
	}
	void add(int i) {
		add(0,sz,i);
	}
	int query(int l, int r, int lx, int rx) {
		if (rx<=l || r<=lx) return 0;
		if (lx<=l && r<=rx) return s;
		int m=(l+r)>>1;
		int lq=L?L->query(l,m,lx,rx):0;
		int rq=R?R->query(m,r,lx,rx):0;
		return lq+rq;
	}
	int query(int l, int r) {
		return query(0,sz,l,r);
	}
};

vector<int> adj[N];
sgt st[N];
int reg[N];

int t=0;
void dfs(int u, int p) {
	L[u]=t++;
	R[u]=L[u];
	for(auto&v:adj[u]) {
		if (v==p) continue;
		dfs(v,u);
		R[u]=max(R[u],R[v]);
	}
}

vector<int> pos[M];
int comp[M];
int cnt[M];

void dfs(int u, int p, int c, int x) {
	c+=reg[u]==x;
	dp1[comp[x]][reg[u]]+=c;
	for(auto&v:adj[u]) {
		if (v==p) continue;
		dfs(v,u,c,x);
	}
}

void solve() {

	int n,r,q; cin>>n>>r>>q;
	forn(i,r) comp[i]=-1;
	cin>>reg[0]; --reg[0];
	forn(i,n-1) {
		int p,r; cin>>p>>r; --p, --r;
		adj[p].pb(i+1); reg[i+1]=r;
	}
	dfs(0,-1);
	forn(i,n) st[reg[i]].add(L[i]);
	forn(i,n) {
		cnt[reg[i]]++;
		pos[reg[i]].pb(i);
	}
	int z=0;
	forn(i,r) {
		if (cnt[i]<=K) continue;
		comp[i]=z++;
		dfs(0,-1,0,i);
	}

	forn(i,q) {
		int r1, r2; cin>>r1>>r2;
		--r1, --r2;
		if (cnt[r1]<=K) {
			int ans=0;
			for(auto&x:pos[r1]) {
				ans+=st[r2].query(L[x],R[x]+1);
			}
			cout<<ans<<'\n';
		} else {
			cout<<dp1[comp[r1]][r2]<<'\n';
		}
		cout.flush();
	}

}

int32_t main() {
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	solve();
}

Compilation message (stderr)

regions.cpp:13:15: warning: overflow in conversion from 'double' to 'int' changes value from '1.0e+18' to '2147483647' [-Woverflow]
   13 | const int inf=1e18;
      |               ^~~~

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