oj.uz

답안 #624125

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
624125 2022-08-07T09:57:00 Z Arinoor Sumtree (INOI20_sumtree) C++17
10 / 100
 448 ms 70584 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){
		cout << "-2\n";
		exit(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){
	int cnt = sz[v] - get(fenC, st[v] + 1, ed[v]);
	ll sum = tag[v] - get(fenS, st[v] + 1, ed[v]);
	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 302 ms 67836 KB Output is correct
2 Correct 296 ms 67660 KB Output is correct
3 Correct 320 ms 67680 KB Output is correct
4 Correct 313 ms 67772 KB Output is correct
5 Correct 279 ms 63716 KB Output is correct
6 Correct 173 ms 36164 KB Output is correct
7 Correct 173 ms 35916 KB Output is correct
8 Correct 172 ms 36000 KB Output is correct
9 Correct 288 ms 60116 KB Output is correct
10 Correct 285 ms 59984 KB Output is correct
11 Correct 282 ms 60060 KB Output is correct
12 Correct 291 ms 58956 KB Output is correct
13 Correct 279 ms 65292 KB Output is correct

Subtask #2
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 171 ms 35572 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 312 ms 70584 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 448 ms 65112 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 302 ms 67836 KB Output is correct
2 Correct 296 ms 67660 KB Output is correct
3 Correct 320 ms 67680 KB Output is correct
4 Correct 313 ms 67772 KB Output is correct
5 Correct 279 ms 63716 KB Output is correct
6 Correct 173 ms 36164 KB Output is correct
7 Correct 173 ms 35916 KB Output is correct
8 Correct 172 ms 36000 KB Output is correct
9 Correct 288 ms 60116 KB Output is correct
10 Correct 285 ms 59984 KB Output is correct
11 Correct 282 ms 60060 KB Output is correct
12 Correct 291 ms 58956 KB Output is correct
13 Correct 279 ms 65292 KB Output is correct
14 Incorrect 171 ms 35572 KB Output isn't correct
15 Halted 0 ms 0 KB -