Submission #469350

# Submission time Handle Problem Language Result Execution time Memory
469350 2021-08-31T15:03:25 Z sinamhdv Sumtree (INOI20_sumtree) C++11
10 / 100
927 ms 54696 KB
// INOI20_sumtree
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int mod = 1000 * 1000 * 1000 + 7;
const int INF = 1e9 + 100;
const ll LINF = 1e18 + 100;

#ifdef DEBUG
#define dbg(x) cout << #x << " = " << (x) << endl << flush;
#define dbgr(s, f) { cout << #s << ": "; for (auto _ = (s); _ != (f); _++) cout << *_ << ' '; cout << endl << flush; }
#else
#define dbg(x) ;
#define dbgr(s, f) ;
#endif
#define fast_io ios::sync_with_stdio(0); cin.tie(0);
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define fr first
#define sc second
#define endl '\n'

const int MAXN = 200100;
const int MAXF = 500100;
const int LOGN = 25;

inline int poww(int a, int b)
{
	int res = 1;
	for (; b; a = (ll)a * a % mod, b /= 2) if (b & 1) res = (ll)res * a % mod;
	return res;
}

int n, rt, q;
vector<int> adj[MAXN];
int bad, ans;
int sttime[MAXN], fntime[MAXN], timer, h[MAXN];
int lbl[MAXN], val[MAXN], cnt[MAXN];
int lpar[LOGN][MAXN];
int fact[MAXF], finv[MAXF];

inline int comb(int n, int k)
{
	return (fact[n] * (ll)finv[k] % mod) * finv[n - k] % mod;
}

void dfs1(int v)
{
	sttime[v] = timer++;
	for (int u : adj[v]) if (u != lpar[0][v])
	{
		lpar[0][u] = v;
		h[u] = h[v] + 1, dfs1(u);
	}
	fntime[v] = timer;
}

struct FEN
{
	ll fen[MAXN];

	inline void addind(int i, ll x)
	{
		for (i++; i < MAXN; i += i & -i) fen[i] += x;
	}

	inline ll pget(int i)
	{
		ll res = 0;
		for (i++; i > 0; i -= i & -i) res += fen[i];
		return res;
	}

	inline ll get(int l, int r)
	{
		if (l > r) return 0;
		return pget(r) - pget(l - 1);
	}

	inline void add(int l, int r, ll x)
	{
		addind(l, x);
		addind(r + 1, -x);
	}

} valfen, ancfen;

struct node
{
	int mn, mincnt, lz;
};

struct SEG
{
	node seg[4 * MAXN];

	inline node mrg(const node &lc, const node &rc)
	{
		node res;
		res.mn = min(lc.mn, rc.mn);
		res.mincnt = 0;
		if (lc.mn == res.mn) res.mincnt += lc.mincnt;
		if (rc.mn == res.mn) res.mincnt += rc.mincnt;
		return res;
	}

	inline void pushdown(int v)
	{
		if (seg[v].lz == -1) return;
		FOR(t, 2 * v, 2 * v + 2)
		{
			if (seg[t].mn == seg[v].mn) seg[t].mn = seg[t].lz = seg[v].lz;
		}
		seg[v].lz = -1;
	}

	void build(int v = 1, int l = 0, int r = n - 1)
	{
		if (l == r)
		{
			seg[v] = {0, 1, -1};
			return;
		}
		int mid = (r + l) / 2;
		build(2 * v, l, mid);
		build(2 * v + 1, mid + 1, r);
		seg[v] = mrg(seg[2 * v], seg[2 * v + 1]);
		seg[v].lz = -1;
	}

	void rset(int L, int R, int x, int v = 1, int l = 0, int r = n - 1)
	{
		if (l > R || r < L) return;
		if (l >= L && r <= R)
		{
			seg[v].mn = seg[v].lz = x;
			return;
		}
		int mid = (r + l) / 2;
		pushdown(v);
		rset(L, R, x, 2 * v, l, mid);
		rset(L, R, x, 2 * v + 1, mid + 1, r);
		seg[v] = mrg(seg[2 * v], seg[2 * v + 1]);
	}

	node getmin(int L, int R, int v = 1, int l = 0, int r = n - 1)
	{
		if (l > R || r < L) return {INF, 0, 0};
		if (l >= L && r <= R) return seg[v];
		int mid = (r + l) / 2;
		pushdown(v);
		return mrg(getmin(L, R, 2 * v, l, mid), getmin(L, R, 2 * v + 1, mid + 1, r));
	}

} seg;

inline int getpar(int x, int d)
{
	FOR(i, 0, LOGN) if (d >> i & 1) x = lpar[i][x];
	return x;
}

inline void addans(int i)
{
	if (val[i] < 0) bad++;
	else ans = (ll)ans * comb(val[i] + cnt[i] - 1, cnt[i] - 1) % mod;
}

inline void remans(int i)
{
	if (val[i] < 0) bad--;
	else ans = (ll)ans * poww(comb(val[i] + cnt[i] - 1, cnt[i] - 1), mod - 2) % mod;
}

inline void updateval(int v)
{
	ll nw = lbl[v] - valfen.get(sttime[v] + 1, fntime[v] - 1);
	valfen.addind(sttime[v], nw - val[v]);
	val[v] = nw;
}

inline int findanc(int v)
{
	int l = 0, r = h[v] + 1;
	int cur = ancfen.pget(sttime[v]);
	while (r - l > 1)
	{
		int mid = (r + l) / 2;
		int x = getpar(v, mid);
		if (ancfen.pget(sttime[x]) == cur) l = mid;
		else r = mid;
	}
	return getpar(v, l);
}

int32_t main(void)
{
	fast_io;

	fact[0] = 1;
	FOR(i, 1, MAXF) fact[i] = fact[i - 1] * (ll)i % mod;
	finv[MAXF - 1] = poww(fact[MAXF - 1], mod - 2);
	for (int i = MAXF - 2; i >= 0; i--) finv[i] = (ll)finv[i + 1] * (i + 1) % mod;

	cin >> n >> rt;
	FOR(i, 0, n - 1)
	{
		int x, y;
		cin >> x >> y;
		adj[x].pb(y);
		adj[y].pb(x);
	}

	dfs1(1);

	FOR(i, 1, LOGN) FOR(j, 1, n + 1) lpar[i][j] = lpar[i - 1][lpar[i - 1][j]];

	ans = comb(n + rt - 1, n - 1);
	cout << ans << endl;
	ancfen.add(0, n - 1, 1);
	lbl[1] = val[1] = rt;
	cnt[1] = n;
	seg.build();

	cin >> q;
	while (q--)
	{
		int op, v;
		cin >> op >> v;
		if (op == 1)	// add
		{
			int x;
			cin >> x;
			lbl[v] = x;

			// update anc
			int l = findanc(v);
			ancfen.add(sttime[v], fntime[v] - 1, 1);

			remans(l);

			// update cnt
			int c = seg.getmin(sttime[v], fntime[v] - 1).mincnt;
			seg.rset(sttime[v], fntime[v] - 1, sttime[v]);
			cnt[l] -= c;
			cnt[v] += c;

			// update val
			updateval(v);
			updateval(l);

			addans(v);
			addans(l);
		}
		else	// rem
		{
			ancfen.add(sttime[v], fntime[v] - 1, -1);
			int l = findanc(v);

			remans(l);
			remans(v);

			int c = seg.getmin(sttime[v], fntime[v] - 1).mincnt;
			seg.rset(sttime[v], fntime[v] - 1, sttime[l]);
			cnt[l] += c;
			cnt[v] = 0;

			valfen.addind(sttime[v], -val[v]);
			lbl[v] = val[v] = 0;
			updateval(l);

			addans(l);
		}

		ans = (mod + ans % mod) % mod;
		if (bad) cout << "0\n";
		else cout << ans << endl;
	}

	return 0;
}


# Verdict Execution time Memory Grader output
1 Correct 167 ms 49844 KB Output is correct
2 Correct 165 ms 49836 KB Output is correct
3 Correct 158 ms 49892 KB Output is correct
4 Correct 172 ms 49868 KB Output is correct
5 Correct 144 ms 46660 KB Output is correct
6 Correct 14 ms 9804 KB Output is correct
7 Correct 14 ms 9644 KB Output is correct
8 Correct 14 ms 9688 KB Output is correct
9 Correct 161 ms 43728 KB Output is correct
10 Correct 159 ms 43680 KB Output is correct
11 Correct 171 ms 43788 KB Output is correct
12 Correct 166 ms 42564 KB Output is correct
13 Correct 154 ms 47056 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 13 ms 9164 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 213 ms 54696 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 927 ms 50252 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 167 ms 49844 KB Output is correct
2 Correct 165 ms 49836 KB Output is correct
3 Correct 158 ms 49892 KB Output is correct
4 Correct 172 ms 49868 KB Output is correct
5 Correct 144 ms 46660 KB Output is correct
6 Correct 14 ms 9804 KB Output is correct
7 Correct 14 ms 9644 KB Output is correct
8 Correct 14 ms 9688 KB Output is correct
9 Correct 161 ms 43728 KB Output is correct
10 Correct 159 ms 43680 KB Output is correct
11 Correct 171 ms 43788 KB Output is correct
12 Correct 166 ms 42564 KB Output is correct
13 Correct 154 ms 47056 KB Output is correct
14 Incorrect 13 ms 9164 KB Output isn't correct
15 Halted 0 ms 0 KB -