Submission #370194

#	Time	Username	Problem	Language	Result	Execution time	Memory
370194		soroush	Zagrade (COI17_zagrade)	C++11	100 / 100	1423 ms	43904 KiB

zagrade

/*
#pragma GCC optimize("O2")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,sse,sse2,fma")
*/
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int , int> pii;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int maxn = 3e5 + 10;
const ll mod = 1e9+7;
const ld PI = acos((ld)-1);

#define pb push_back
#define endl '\n'
#define dokme(x) cout << x , exit(0)
#define migmig ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define ms(x , y) memset(x , y , sizeof x)
ll pw(ll a, ll b, ll md = mod){ll res = 1;while(b){if(b&1){res=(a*res)%md;}a=(a*a)%md;b>>=1;}return(res);}


int n , op[maxn] , sz[maxn] , cnt[maxn];
vector < int > adj[maxn];
string s;
bool hide[maxn];
ll ans = 0;

void plant(int v ,int p = 0){
	sz[v] = 1;
	for(auto u : adj[v])if(!hide[u] and u^p)
		plant(u , v) , sz[v] += sz[u];
}

int cen(int v , int n , int par = 0 , bool found = 0){
	while(!found){
		found = 1;
		for(auto u : adj[v])if(u ^ par and !hide[u] and sz[u] * 2 > n){
			par = v , v = u , found = 0;
			break;
		}
	}
	return(v);
}

void add(int v , int h , int mx){
	h += op[v];
	if(h >= mx)cnt[h] ++ , mx = h;
	hide[v] = 1;
	for(auto u : adj[v])if(!hide[u])
		add(u , h , mx);
	hide[v] = 0;
}

void rm(int v , int h , int mx){
	h += op[v];
	if(h >= mx)cnt[h] -- , mx = h;
	hide[v] = 1;
	for(auto u : adj[v])if(!hide[u])
		rm(u , h , mx);
	hide[v] = 0;
}

ll chk(int v , int h = 0 , int mn = 0){
	h += op[v];
	ll ans = 0;
	if(h <= mn)ans += cnt[-h] , mn = h;
	hide[v] = 1;
	for(auto u : adj[v])if(!hide[u])
		ans += chk(u , h , mn);
	hide[v] = 0;
	return ans;
}

ll solve(int v){
	ll ans = 0;
	if(op[v] == 1){
		cnt[1] ++;
		for(auto u : adj[v])if(!hide[u])
			add(u , 1 , 1);
		for(auto u : adj[v])if(!hide[u])
			rm(u , 1 , 1), ans += chk(u) , add(u , 1 , 1);
		for(auto u : adj[v])if(!hide[u])
			rm(u , 1 , 1);
		cnt[1] --;
	}
	else{
		for(auto u : adj[v])if(!hide[u])
			add(u , -1 , 0);
		ans += cnt[0];
		for(auto u : adj[v])if(!hide[u])
			rm(u , -1 , 0), ans += chk(u) , add(u , -1 , 0);
		for(auto u : adj[v])if(!hide[u])
			rm(u , -1 , 0);
	}
	return(ans);
}

void decomp(int v){
	plant(v);
	v = cen(v , sz[v]);
	hide[v] = 1;
	ans += solve(v);
	for(auto u : adj[v])
		if(!hide[u])decomp(u);
}

int32_t main(){
	migmig;
	cin >> n >> s;
	for(int i = 1 ; i <= n ; i ++)op[i] = (s[i - 1] == '(' ? 1 : -1);
	for(int i = 1 ; i <  n ; i ++){
		int u , v;
		cin >> u >> v;
		adj[u].pb(v) , adj[v].pb(u);
	}
	decomp(1);
	cout << ans;
	return(0);
}

• Subtask 1: 10 / 10
• Subtask 2: 30 / 30
• Subtask 3: 60 / 60