oj.uz

Submission #624129

# Submission time Handle Problem Language Result Execution time Memory
624129 2022-08-07T10:02:56 Z Arinoor Sumtree (INOI20_sumtree) C++17
10 / 100
 524 ms 71584 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 or b < 0){
		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){
	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

# Verdict Execution time Memory Grader output
1 Correct 323 ms 67820 KB Output is correct
2 Correct 300 ms 67776 KB Output is correct
3 Correct 311 ms 67788 KB Output is correct
4 Correct 309 ms 67716 KB Output is correct
5 Correct 294 ms 63800 KB Output is correct
6 Correct 180 ms 36072 KB Output is correct
7 Correct 170 ms 35964 KB Output is correct
8 Correct 176 ms 35932 KB Output is correct
9 Correct 298 ms 60100 KB Output is correct
10 Correct 278 ms 60124 KB Output is correct
11 Correct 286 ms 60044 KB Output is correct
12 Correct 288 ms 58848 KB Output is correct
13 Correct 313 ms 65260 KB Output is correct

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 175 ms 35548 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 345 ms 71584 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 524 ms 65304 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 323 ms 67820 KB Output is correct
2 Correct 300 ms 67776 KB Output is correct
3 Correct 311 ms 67788 KB Output is correct
4 Correct 309 ms 67716 KB Output is correct
5 Correct 294 ms 63800 KB Output is correct
6 Correct 180 ms 36072 KB Output is correct
7 Correct 170 ms 35964 KB Output is correct
8 Correct 176 ms 35932 KB Output is correct
9 Correct 298 ms 60100 KB Output is correct
10 Correct 278 ms 60124 KB Output is correct
11 Correct 286 ms 60044 KB Output is correct
12 Correct 288 ms 58848 KB Output is correct
13 Correct 313 ms 65260 KB Output is correct
14 Incorrect 175 ms 35548 KB Output isn't correct
15 Halted 0 ms 0 KB -