oj.uz

Submission #369371

# Submission time Handle Problem Language Result Execution time Memory
369371 2021-02-21T13:01:32 Z AmineWeslati Regions (IOI09_regions) C++14
100 / 100
 4588 ms 55760 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;
int N,R,Q; 
vi a(MX),adj[MX],cnt(MX,0),vec[MX],vec2[MX],in(MX),out(MX);
V<ll>mp[MX];

//mp[x][y]
void dfs(int u, int c, ll 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]));
}


ll 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{
    		ll 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

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 22252 KB Output is correct
2 Correct 16 ms 22252 KB Output is correct
3 Correct 18 ms 22252 KB Output is correct
4 Correct 20 ms 22252 KB Output is correct
5 Correct 25 ms 22252 KB Output is correct
6 Correct 32 ms 22508 KB Output is correct
7 Correct 32 ms 22416 KB Output is correct
8 Correct 36 ms 22380 KB Output is correct
9 Correct 72 ms 22764 KB Output is correct
10 Correct 101 ms 22772 KB Output is correct
11 Correct 104 ms 22892 KB Output is correct
12 Correct 202 ms 23532 KB Output is correct
13 Correct 244 ms 23020 KB Output is correct
14 Correct 363 ms 23660 KB Output is correct
15 Correct 349 ms 26012 KB Output is correct

Subtask #2
85.0 / 85.0

# Verdict Execution time Memory Grader output
1 Correct 2220 ms 26220 KB Output is correct
2 Correct 2112 ms 24932 KB Output is correct
3 Correct 3484 ms 28396 KB Output is correct
4 Correct 381 ms 23660 KB Output is correct
5 Correct 480 ms 25184 KB Output is correct
6 Correct 778 ms 28012 KB Output is correct
7 Correct 1548 ms 27672 KB Output is correct
8 Correct 1528 ms 39012 KB Output is correct
9 Correct 2770 ms 30068 KB Output is correct
10 Correct 3951 ms 55760 KB Output is correct
11 Correct 4588 ms 29300 KB Output is correct
12 Correct 1784 ms 31084 KB Output is correct
13 Correct 2419 ms 31524 KB Output is correct
14 Correct 3128 ms 34348 KB Output is correct
15 Correct 4072 ms 36572 KB Output is correct
16 Correct 3576 ms 43756 KB Output is correct
17 Correct 3683 ms 45452 KB Output is correct