oj.uz

답안 #624132

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
624132 2022-08-07T10:05:22 Z Arinoor Sumtree (INOI20_sumtree) C++17
10 / 100
 330 ms 67808 KB 
#include <bits/stdc++.h>
using namespace std;

#define pb				push_back
#define mp				make_pair
#define fi				first
#define se				second
#define all(x)			x.begin(), x.end()
#define bug(x)			cout << #x << " : " << x << '\n'
#define ios				ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0)

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

const int maxn = 1e6 + 10;
const int maxlg = 19;
const int maxf = 1e6 + 10;
const int mod = 1e9 + 7;
const int inf = 1e9 + 10;

int n, fact[maxf], invfact[maxf];
int val[maxn], tag[maxn];
int par[maxn][maxlg], sz[maxn], st[maxn], ed[maxn], tme = 1;
ll fenC[maxn], fenS[maxn], fenP[maxn];
vector<int> G[maxn];

int add(int a, int b){
	int c = a + b;
	if(c >= mod) c -= mod;
	if(c < 0) c += mod;
	return c;
}

int mul(int a, int b){
	return 1ll * a * b % mod;
}

int pwr(int a, int b){
	int res = 1;
	for(; b; b >>= 1, a = mul(a, a)) if(b & 1) res = mul(res, a);
	return res;
}

int inv(int a){
	return pwr(a, mod - 2);
}

int C(ll a, ll b){
	if(a > b)
		return 0;
	if(b >= maxf){
		return 0;
	}
	return mul(fact[b], mul(invfact[a], invfact[b - a]));
}

void update_fact(){
	fact[0] = invfact[0] = 1;
	for(int i = 1; i < maxf; i ++){
		fact[i] = mul(fact[i - 1], i);
		invfact[i] = inv(fact[i]);
	}
	/*
	invfact[maxf - 1] = inv(fact[maxf - 1]);
	for(int i = maxf - 2; ~i; i --)
		invfact[i] = mul(invfact[i + 1], i + 1);
		*/
}

void add(ll *fen, int i, ll x){
	for(; i <= n; i += i & -i)
		fen[i] += x;
}

ll get(ll *fen, int i){
	ll res = 0;
	for(; i; i -= i & -i)
		res += fen[i];
	return res;
}

ll get(ll *fen, int l, int r){
	return get(fen, r) - get(fen, l - 1);
}

void dfs(int v, int p = 0){
	par[v][0] = p;
	for(int i = 1; i < maxlg and par[v][i - 1]; i ++)
		par[v][i] = par[par[v][i - 1]][i - 1];
	st[v] = tme;
	sz[v] = 1;
	for(int u : G[v]){
		if(u ^ p){
			tme ++;
			dfs(u, v);
			sz[v] += sz[u];
		}
	}
	ed[v] = tme;
}

int get_val(int v){
	ll cnt = sz[v] - get(fenC, st[v] + 1, ed[v]);
	ll sum = tag[v] - get(fenS, st[v] + 1, ed[v]);
  	if(cnt - 1 < 0){
      cout << "-2\n";
      exit(0);
    }
	return C(cnt - 1, cnt + sum - 1);
}

int find(int v){
	int x = get(fenP, st[v]);
	for(int i = maxlg - 1; ~i; i --){
		int u = par[v][i];
		if(!u) continue;
		if(get(fenP, st[u]) == x)
			v = u;
	}
	return par[v][0];
}

int main(){
	ios;
	update_fact();
	int r;
	cin >> n >> r;
	for(int i = 0; i < n - 1; i ++){
		int u, v;
		cin >> u >> v;
		G[u].pb(v);
		G[v].pb(u);
	}
	dfs(1);
	memset(tag, -1, sizeof tag);
	tag[1] = r;
	add(fenP, st[1] + 1, 1); add(fenP, ed[1] + 1, -1);
	for(int i = 2; i <= n; i ++)
		val[i] = 1;
	val[1] = get_val(1);
	int ans = val[1];
	cout << ans << '\n';
	int q; cin >> q;
	int Cnt = 0;
	while(q--){
		int t, v;
		cin >> t >> v;
		if(t == 1){
			int x; cin >> x;
			tag[v] = x;
			val[v] = get_val(v);
			if(val[v])
				ans = mul(ans, val[v]);
			else
				Cnt ++;
			int cnt = sz[v] - get(fenC, st[v] + 1, ed[v]);
			add(fenC, st[v], cnt);
			ll sum = tag[v] - get(fenS, st[v] + 1, ed[v]);
			add(fenS, st[v], sum);
			add(fenP, st[v] + 1, 1); add(fenP, ed[v] + 1, -1);
			int p = find(v);
			if(inv(val[p]))
				ans = mul(ans, inv(val[p]));
			else
				Cnt --;
			val[p] = get_val(p);
			if(val[p])
				ans = mul(ans, val[p]);
			else
				Cnt ++;
		}
		else{
			if(inv(val[v]))
				ans = mul(ans, inv(val[v]));
			else
				Cnt --;
			val[v] = 1;
			int cnt = sz[v] - get(fenC, st[v] + 1, ed[v]);
			add(fenC, st[v], -cnt);
			ll sum = tag[v] - get(fenS, st[v] + 1, ed[v]);
			add(fenS, st[v], -sum);
			add(fenP, st[v] + 1, -1); add(fenP, ed[v] + 1, 1);
			int p = find(v);
			if(inv(val[p]))
				ans = mul(ans, inv(val[p]));
			else
				Cnt --;
			val[p] = get_val(p);
			if(val[p])
				ans = mul(ans, val[p]);
			else
				Cnt ++;
			tag[v] = -1;
		}
		if(Cnt)
			cout << "0\n";
		else
			cout << ans << '\n';
	}
}

Subtask #1
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 310 ms 67772 KB Output is correct
2 Correct 303 ms 67684 KB Output is correct
3 Correct 330 ms 67808 KB Output is correct
4 Correct 304 ms 67712 KB Output is correct
5 Correct 292 ms 63704 KB Output is correct
6 Correct 180 ms 36132 KB Output is correct
7 Correct 175 ms 35964 KB Output is correct
8 Correct 179 ms 35888 KB Output is correct
9 Correct 302 ms 60136 KB Output is correct
10 Correct 288 ms 60016 KB Output is correct
11 Correct 302 ms 60100 KB Output is correct
12 Correct 275 ms 58896 KB Output is correct
13 Correct 286 ms 65228 KB Output is correct

Subtask #2
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 178 ms 35504 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 306 ms 67788 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 300 ms 64752 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 310 ms 67772 KB Output is correct
2 Correct 303 ms 67684 KB Output is correct
3 Correct 330 ms 67808 KB Output is correct
4 Correct 304 ms 67712 KB Output is correct
5 Correct 292 ms 63704 KB Output is correct
6 Correct 180 ms 36132 KB Output is correct
7 Correct 175 ms 35964 KB Output is correct
8 Correct 179 ms 35888 KB Output is correct
9 Correct 302 ms 60136 KB Output is correct
10 Correct 288 ms 60016 KB Output is correct
11 Correct 302 ms 60100 KB Output is correct
12 Correct 275 ms 58896 KB Output is correct
13 Correct 286 ms 65228 KB Output is correct
14 Incorrect 178 ms 35504 KB Output isn't correct
15 Halted 0 ms 0 KB -