Submission #765977

#	Time	Username	Problem	Language	Result	Execution time	Memory
765977		vjudge1	Untitled (POI11_rot)	C++17	100 / 100	282 ms	44188 KiB

Main

#include <bits/stdc++.h>
 
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
#define all(a) a.begin() , a.end()
#define F first
#define S second
#define int ll

using namespace std;
using ll = long long;
 
const int N = 5e5+5 , inf = 2e9 + 7;
const ll INF = 1e18 ,   mod = 1e9+7;	

int ans[N] , n , mxson[N] , sz[N] , t[N] , m; 
vector<int> g[N];

void precalc(int v , int pr){
	if(v <= n) sz[v] = 1;
	for(int to : g[v]){
		if(to != pr){
			precalc(to,v);
			sz[v] += sz[to];
			if(sz[to] > sz[mxson[v]]) mxson[v] = to;
		}
	}
}

void upd(int i, int x){
    for(; i <= n; i |= (i + 1)) t[i] += x;
}

int get(int i){
    int res = 0;
    for(; i > 0; i = (i & (i + 1)) - 1) res += t[i];
    return res;
}
int ob;

pair<int,int> calc(int v, int pr){
	if(v <= n) {
		int num = get(v);
		return {num,ob-num};
	}
	int res = 0 , res1 = 0;
	for(int to : g[v]){
		 if(to != pr) {
		 	pair<int,int> a = calc(to,v);
		 	res += a.F;
		 	res1 += a.S;
		 }
	}
	return {res,res1};
}
void del(int v, int pr){
	if(v <= n) upd(v,-1);
	for(int to : g[v]) if(to != pr) del(to,v);
}
void add(int v, int pr){
	if(v <= n) upd(v,1);
	for(int to : g[v]) if(to != pr) add(to,v);
}
void dfs(int v , int pr){
	for(int to : g[v]){
		if(to != pr && to != mxson[v]){
			dfs(to,v);
			del(to,v);
		}
	}
	if(mxson[v]) {
		dfs(mxson[v],v);
		ans[v] += ans[mxson[v]];
	}
	int res = 0 , res1 = 0;
	for(int to : g[v]){
		ob = get(n);
		if(to != pr && to != mxson[v]) {
			pair<int,int> b = calc(to,v);
			res += b.F;
			res1 += b.S;
			add(to,v);
			ans[v] += ans[to];
		}
	}
	if(v <= n) upd(v,1);
	else ans[v] += min(res,res1);
} 
int NUM;
void go(int v){
	int x;
	cin >> x;
	if(x == 0){
		int to = ++NUM;
		g[v].push_back(to);
		g[to].push_back(v);
		go(to);
	} else {
		g[v].push_back(x);
		g[x].push_back(v);
	}
	cin >> x;
	if(x == 0){
		int to = ++NUM;
		g[v].push_back(to);
		g[to].push_back(v);
		go(to);
	} else {
		g[v].push_back(x);
		g[x].push_back(v);
	}
}
void solve(){
	cin >> n;
	NUM = n+1;
	int a; cin >> a;
	go(n+1);
	precalc(n+1,0);
	dfs(n+1,0);
	cout << ans[n+1] << "\n";
}
/*

*/
signed main(){
	ios;
	solve();
	return 0;
} 	

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 9 / 9
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 10 / 10