oj.uz

Submission #943796

# Submission time Handle Problem Language Result Execution time Memory
943796 2024-03-12T00:50:21 Z daoquanglinh2007 Arboras (RMI20_arboras) C++17
100 / 100
 792 ms 59160 KB 
#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pii pair <int, int>
#define fi first
#define se second
#define mp make_pair

const int NM = 1e5, LOG = 16, MOD = 1e9+7;

struct node{
	int sz, f, g;
};

struct tag{
	pii f, g;
	tag(){
		f = g = mp(1, 0);
	}
	tag(pii y, pii z){
		f = y, g = z;
	}
};

int n, q, p[NM+5], d[NM+5], dep[NM+5], sumd[NM+5], sz[NM+5], f[NM+5], g[NM+5], jump[NM+5][LOG+5], cur = 0;
vector <int> son[NM+5];
int head[NM+5], timer = 0, tin[NM+5], tour[NM+5], tout[NM+5];
node st[4*NM+5];
tag lazy[4*NM+5];

void dfs_sz(int u){
	dep[u] = (u == 1 ? 0 : dep[p[u]]+1);
	sumd[u] = sumd[p[u]]+d[u];
	sz[u] = 1;
	f[u] = g[u] = 0;
	for (int v : son[u]){
		dfs_sz(v);
		sz[u] += sz[v];
		if (f[v]+d[v] > f[u]){
			g[u] = f[u];
			f[u] = f[v]+d[v];
		}
		else if (f[v]+d[v] > g[u]){
			g[u] = f[v]+d[v];
		}
	}
	cur += 2*sumd[u];
}

void build_sparse(){
	for (int i = 1; i <= n; i++) jump[i][0] = p[i];
	for (int j = 1; j <= LOG; j++)
		for (int i = 1; i <= n; i++)
			jump[i][j] = jump[jump[i][j-1]][j-1];
}

void dfs_hld(int u){
	tin[u] = ++timer;
	tour[timer] = u;
	int mxVtx = -1;
	for (int v : son[u]){
		if (mxVtx == -1 || sz[v] > sz[mxVtx]) mxVtx = v;
	}
	if (mxVtx != -1){
		head[mxVtx] = head[u];
		dfs_hld(mxVtx);
	}
	for (int v : son[u]){
		if (v == mxVtx) continue;
		head[v] = v;
		dfs_hld(v);
	}
	tout[u] = timer;
}

node operator + (node a, node b){
	node c;
	c.sz = a.sz+b.sz;
	c.f = a.f+b.f;
	c.g = a.g+b.g;
	return c;
}

void build(int id, int l, int r){
	if (l == r){
		int u = tour[l];
		st[id].sz = 1;
		st[id].f = f[u]+sumd[u];
		st[id].g = g[u]+sumd[u];
		return;
	}
	int mid = (l+r)/2;
	build(2*id, l, mid);
	build(2*id+1, mid+1, r);
	st[id] = st[2*id]+st[2*id+1];
}

void apply(int id, tag T){
	if (T.f.fi == 1) st[id].f += T.f.se*st[id].sz; else st[id].f = T.f.se*st[id].sz;
	if (T.g.fi == 1) st[id].g += T.g.se*st[id].sz; else st[id].g = T.g.se*st[id].sz;
}

pii operator + (pii a, pii b){
	pii c;
	if (b.fi == 2) c = mp(2, b.se);
	else if (a.fi == 2) c = mp(2, a.se+b.se);
	else c = mp(1, a.se+b.se);
	return c;
}

tag operator + (tag a, tag b){
	tag c;
	c.f = a.f+b.f;
	c.g = a.g+b.g;
	return c;
}

void down(int id){
	apply(2*id, lazy[id]); apply(2*id+1, lazy[id]);
	lazy[2*id] = lazy[2*id]+lazy[id]; lazy[2*id+1] = lazy[2*id+1]+lazy[id];
	lazy[id] = tag();
}

void swap(int id, int l, int r, int i){
	if (i < l || i > r) return;
	if (l == r){
		swap(st[id].f, st[id].g);
		return;
	}
	down(id);
	int mid = (l+r)/2;
	swap(2*id, l, mid, i);
	swap(2*id+1, mid+1, r, i);
	st[id] = st[2*id]+st[2*id+1];
}

void cover(int id, int l, int r, int u, int v, pii P){
	if (v < l || u > r) return;
	if (l >= u && r <= v){
		pii x = mp(1, 0), y = mp(1, 0);
		if (P.fi != -1) x = mp(2, P.fi);
		if (P.se != -1) y = mp(2, P.se);
		tag T = tag(x, y);
		apply(id, T);
		lazy[id] = lazy[id]+T;
		return;
	}
	down(id);
	int mid = (l+r)/2;
	cover(2*id, l, mid, u, v, P);
	cover(2*id+1, mid+1, r, u, v, P);
	st[id] = st[2*id]+st[2*id+1];
}

void add(int id, int l, int r, int u, int v, pii P){
	if (v < l || u > r) return;
	if (l >= u && r <= v){
		tag T = tag(mp(1, P.fi), mp(1, P.se));
		apply(id, T);
		lazy[id] = lazy[id]+T;
		return;
	}
	down(id);
	int mid = (l+r)/2;
	add(2*id, l, mid, u, v, P);
	add(2*id+1, mid+1, r, u, v, P);
	st[id] = st[2*id]+st[2*id+1];
}

node get(int id, int l, int r, int i){
	if (l == r) return st[id];
	down(id);
	int mid = (l+r)/2;
	if (i <= mid) return get(2*id, l, mid, i);
	return get(2*id+1, mid+1, r, i);
}

void buff_f(int u, int a, int val){
	while (true){
		if (head[u] == head[a]){
			cover(1, 1, n, tin[a], tin[u], mp(val, -1));
			break;
		}
		cover(1, 1, n, tin[head[u]], tin[u], mp(val, -1));
		u = p[head[u]];
	}
}

void update(int u, int su, int a, int val){
	if (u == 0 || dep[u] < dep[a]) return;
	vector <int> arr = {};
	while (true){
		if (get(1, 1, n, tin[u]).f == get(1, 1, n, tin[su]).f){
			int v = u, tmp = get(1, 1, n, tin[su]).f;
			for (int i = LOG; i >= 0; i--){
				if (jump[v][i] == 0 || dep[jump[v][i]] < dep[a]) continue;
				if (get(1, 1, n, tin[jump[v][i]]).f == tmp) v = jump[v][i];
			}
			buff_f(u, v, val);
			u = p[v];
		}
		if (u == 0 || dep[u] < dep[a]) break;
		arr.push_back(u);
		su = u;
		u = p[u];
	}
	for (int u : arr){
		swap(1, 1, n, tin[u]);
		cover(1, 1, n, tin[u], tin[u], mp(val, -1));
	}
}

signed main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	cin >> n;
	for (int i = 2; i <= n; i++){
		cin >> p[i];
		p[i]++;
		son[p[i]].push_back(i);
	}
	for (int i = 2; i <= n; i++){
		cin >> d[i];
	}
	dfs_sz(1);
	build_sparse();
	head[1] = 1;
	dfs_hld(1);
	build(1, 1, n);
	
	cout << (st[1].f+st[1].g-cur)%MOD << '\n';
	cin >> q;
	while (q--){
		int x, y; cin >> x >> y;
		x++;
		cur += 2*sz[x]*y;
		int u = x, tmp = get(1, 1, n, tin[x]).f+y;
		for (int i = LOG; i >= 0; i--){
			if (jump[u][i] == 0) continue;
			if (tmp > get(1, 1, n, tin[jump[u][i]]).f) u = jump[u][i];
		}
		update(p[x], x, u, tmp);
		u = p[u];
		if (u > 0 && tmp > get(1, 1, n, tin[u]).g){
			cover(1, 1, n, tin[u], tin[u], mp(-1, tmp));
		}
		add(1, 1, n, tin[x], tout[x], mp(y, y));
		cout << (st[1].f+st[1].g-cur)%MOD << '\n';
	}
	return 0;
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 27228 KB Output is correct
2 Correct 8 ms 27228 KB Output is correct
3 Correct 6 ms 27228 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 556 ms 54604 KB Output is correct
2 Correct 346 ms 53192 KB Output is correct
3 Correct 305 ms 53584 KB Output is correct

Subtask #3
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 769 ms 56492 KB Output is correct
2 Correct 674 ms 58828 KB Output is correct
3 Correct 601 ms 55312 KB Output is correct

Subtask #4
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 27228 KB Output is correct
2 Correct 8 ms 27228 KB Output is correct
3 Correct 6 ms 27228 KB Output is correct
4 Correct 556 ms 54604 KB Output is correct
5 Correct 346 ms 53192 KB Output is correct
6 Correct 305 ms 53584 KB Output is correct
7 Correct 769 ms 56492 KB Output is correct
8 Correct 674 ms 58828 KB Output is correct
9 Correct 601 ms 55312 KB Output is correct
10 Correct 792 ms 56316 KB Output is correct
11 Correct 692 ms 58612 KB Output is correct
12 Correct 573 ms 54708 KB Output is correct
13 Correct 755 ms 58356 KB Output is correct
14 Correct 723 ms 59160 KB Output is correct