oj.uz

Submission #624130

# Submission time Handle Problem Language Result Execution time Memory
624130 2022-08-07T10:03:38 Z Arinoor Sumtree (INOI20_sumtree) C++17
10 / 100
 526 ms 144656 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){
	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 302 ms 67732 KB Output is correct
2 Correct 319 ms 67752 KB Output is correct
3 Correct 313 ms 67752 KB Output is correct
4 Correct 307 ms 67672 KB Output is correct
5 Correct 277 ms 63720 KB Output is correct
6 Correct 177 ms 36188 KB Output is correct
7 Correct 184 ms 35944 KB Output is correct
8 Correct 175 ms 35900 KB Output is correct
9 Correct 289 ms 60108 KB Output is correct
10 Correct 301 ms 59924 KB Output is correct
11 Correct 290 ms 60100 KB Output is correct
12 Correct 270 ms 59144 KB Output is correct
13 Correct 290 ms 65308 KB Output is correct

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 173 ms 35552 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 20.0

# Verdict Execution time Memory Grader output
1 Runtime error 377 ms 144656 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 526 ms 65468 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 302 ms 67732 KB Output is correct
2 Correct 319 ms 67752 KB Output is correct
3 Correct 313 ms 67752 KB Output is correct
4 Correct 307 ms 67672 KB Output is correct
5 Correct 277 ms 63720 KB Output is correct
6 Correct 177 ms 36188 KB Output is correct
7 Correct 184 ms 35944 KB Output is correct
8 Correct 175 ms 35900 KB Output is correct
9 Correct 289 ms 60108 KB Output is correct
10 Correct 301 ms 59924 KB Output is correct
11 Correct 290 ms 60100 KB Output is correct
12 Correct 270 ms 59144 KB Output is correct
13 Correct 290 ms 65308 KB Output is correct
14 Incorrect 173 ms 35552 KB Output isn't correct
15 Halted 0 ms 0 KB -