Submission #369370

# Submission time Handle Problem Language Result Execution time Memory
369370 2021-02-21T12:55:38 Z AmineWeslati Regions (IOI09_regions) C++14
85 / 100
4113 ms 33000 KB
//Never stop trying
#include "bits/stdc++.h"
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

typedef long long ll;
typedef string str;
typedef long double ld;
typedef pair<int, int> pi;
#define fi first
#define se second
typedef vector<int> vi;
typedef vector<pi> vpi;
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define endl "\n"
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)

const int MOD = 1e9 + 7; //998244353
const ll INF = 1e18;
const int MX = 2e5 + 10;
const int nx[4] = {0, 0, 1, -1}, ny[4] = {1, -1, 0, 0}; //right left down up

template<class T> using V = vector<T>;
template<class T> bool ckmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); } // divide a by b rounded up
//constexpr int log2(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
//mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
ll random(ll a, ll b){
    return a + rng() % (b - a + 1);
}
#ifndef LOCAL  
#define cerr if(false) cerr
#endif
#define dbg(x) cerr << #x << " : " << x << endl; 
#define dbgs(x,y) cerr << #x << " : " << x << " / " << #y << " : " << y << endl;
#define dbgv(v) cerr << #v << " : " << "[ "; for(auto it : v) cerr << it << ' '; cerr << ']' << endl;
#define here() cerr << "here" << endl;

void IO() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin); 
    freopen("output.txt", "w", stdout);
#endif
}
/////////////////////////ONLY CLEAN CODES ALLOWED/////////////////////////

const int C=400,MX2=25000;
int N,R,Q; 
vi a(MX),adj[MX],cnt(MX2,0),vec[MX2],vec2[MX2],in(MX),out(MX),mp[MX2];

//mp[x][y]
void dfs(int u, int c, int nb){
	for(auto v: adj[u]){
		mp[c][a[v]]+=nb;
		dfs(v,c,nb+(a[v]==c));
	}
}
void precompute1(){ 
	FOR(i,1,R+1) if(cnt[i]>C){
		mp[i].assign(R+1,0);
		dfs(1,i,(a[1]==i));
	}
}

//in[u],out[u]
//vec2[c]
int cntr=0;
void euler(int u=1, int p=1){
	in[u]=++cntr;
	for(auto v: adj[u]) euler(v,u);
	out[u]=cntr;
}
void precompute2(){ 
	euler();
	FOR(i,1,N+1) vec2[a[i]].pb(in[i]);
	FOR(i,1,R+1) sort(all(vec2[i]));
}


int solve(int l, int r, int c){
	if(l>r) return 0;
	return upper_bound(all(vec2[c]),r)-lower_bound(all(vec2[c]),l);
}

int main() {
    boost; IO();

    cin>>N>>R>>Q;
    FOR(i,1,N+1){
    	if(i>1){
    		int j; cin>>j;
    		adj[j].pb(i);
    	}
    	cin>>a[i];
    	vec[a[i]].pb(i);
    	cnt[a[i]]++;
    }

    precompute1(); //(N/C)*N
    precompute2(); 

    //Q*C*lg(N)
    while(Q--){ 
    	int x,y; cin>>x>>y;
    	if(cnt[x]>C){
    		cout << mp[x][y] << endl;
    		cout.flush();
    	}
    	else{
    		int ans=0;
    		for(auto u: vec[x]){
    			int l=in[u],r=out[u];
    			ans+=solve(l+1,r,y);
    		}
    		cout << ans << endl;
    		cout.flush();
    	}
    }

    return 0;
}
//Change your approach 
# Verdict Execution time Memory Grader output
1 Correct 7 ms 9196 KB Output is correct
2 Correct 8 ms 9196 KB Output is correct
3 Correct 9 ms 9196 KB Output is correct
4 Correct 10 ms 9324 KB Output is correct
5 Correct 11 ms 9324 KB Output is correct
6 Correct 27 ms 9344 KB Output is correct
7 Correct 50 ms 9324 KB Output is correct
8 Correct 43 ms 9324 KB Output is correct
9 Correct 54 ms 9836 KB Output is correct
10 Correct 113 ms 9708 KB Output is correct
11 Correct 178 ms 10008 KB Output is correct
12 Correct 160 ms 10348 KB Output is correct
13 Correct 182 ms 9964 KB Output is correct
14 Correct 358 ms 10476 KB Output is correct
15 Correct 315 ms 12908 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1909 ms 13324 KB Output is correct
2 Correct 2061 ms 11912 KB Output is correct
3 Correct 3172 ms 15280 KB Output is correct
4 Correct 358 ms 10664 KB Output is correct
5 Correct 435 ms 12268 KB Output is correct
6 Correct 683 ms 13292 KB Output is correct
7 Correct 1776 ms 13604 KB Output is correct
8 Correct 1463 ms 22144 KB Output is correct
9 Correct 3240 ms 17024 KB Output is correct
10 Correct 3716 ms 33000 KB Output is correct
11 Incorrect 4113 ms 16336 KB Output isn't correct
12 Correct 1812 ms 17948 KB Output is correct
13 Correct 2560 ms 18384 KB Output is correct
14 Correct 2998 ms 19516 KB Output is correct
15 Incorrect 4000 ms 23404 KB Output isn't correct
16 Incorrect 3585 ms 30544 KB Output isn't correct
17 Correct 3408 ms 30572 KB Output is correct