test/data-structure/lazy-lct/aoj-Do-use-segment-tree.test.cpp

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• Last update: 2023-07-20 17:15:06+08:00
• Problem: https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=2450

Depends on

• Link Cut Tree (library/data-structure/lazy-lct.hpp)

Code

#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=2450"

#include <iostream>

#include <limits>

#include <vector>

#include <algorithm>

#include "../../../library/data-structure/lazy-lct.hpp"

using namespace std;
using namespace felix;

struct S {
	int mx = numeric_limits<int>::min();
	int sum = 0;
	int pref = 0, suff = 0;
	int ans = 0;
	int sz = 0;
};

S e() { return S(); }

S op(S a, S b) {
	S c;
	c.mx = max(a.mx, b.mx);
	c.sum = a.sum + b.sum;
	c.pref = max(a.pref, a.sum + b.pref);
	c.suff = max(b.suff, b.sum + a.suff);
	c.ans = max({a.ans, b.ans, a.suff + b.pref});
	c.sz = a.sz + b.sz;
	return c;
}

S reversal(S s) {
	swap(s.pref, s.suff);
	return s;
}

using F = int;

F id() { return numeric_limits<int>::min(); }

S mapping(F f, S s) {
	if(f == id()) {
		return s;
	}
	s.mx = f;
	s.sum = f * s.sz;
	s.pref = s.suff = s.ans = max(f, 0) * s.sz;
	return s;
}

F composition(F a, F b) {
	if(a == id() || b == id()) {
		return a != id() ? a : b;
	}
	return a;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n, q;
	cin >> n >> q;
	vector<S> a(n);
	for(int i = 0; i < n; i++) {
		int x;
		cin >> x;
		a[i].mx = a[i].sum = x;
		a[i].ans = a[i].pref = a[i].suff = max(x, 0);
		a[i].sz = 1;
	}
	lazy_lct<S, e, op, reversal, F, id, mapping, composition> lct(a);
	for(int i = 0; i < n - 1; i++) {
		int u, v;
		cin >> u >> v;
		u--, v--;
		lct.link(u, v);
	}
	while(q--) {
		int type, u, v, w;
		cin >> type >> u >> v >> w;
		u--, v--;
		if(type == 1) {
			lct.apply(u, v, F{w});
		} else {
			S res = lct.prod(u, v);
			cout << (res.ans == 0 ? res.mx : res.ans) << "\n";
		}
	}
	return 0;
}

#line 1 "test/data-structure/lazy-lct/aoj-Do-use-segment-tree.test.cpp"
#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=2450"

#include <iostream>

#include <limits>

#include <vector>

#include <algorithm>

#line 4 "library/data-structure/lazy-lct.hpp"
#include <cassert>


namespace felix {

template<class S,
         S (*e)(),
         S (*op)(S, S),
         S (*reversal)(S),
         class F,
         F (*id)(),
         S (*mapping)(F, S),
         F (*composition)(F, F)>
struct lazy_lct {
public:
	struct node_t {
		S val = e(), sum = e();
		F lz = id();
		bool rev = false;
		int sz = 1;
		node_t* l = nullptr;
		node_t* r = nullptr;
		node_t* p = nullptr;

		node_t() {}
		node_t(const S& s) : val(s), sum(s) {}

		bool is_root() const { return p == nullptr || (p->l != this && p->r != this); }
	};

	lazy_lct() : n(0) {}
	explicit lazy_lct(int _n) : lazy_lct(std::vector<S>(_n, e())) {}
	explicit lazy_lct(const std::vector<S>& v) : n(v.size()) {
		a.reserve(n);
		for(int i = 0; i < n; i++) {
			a.emplace_back(v[i]);
		}
	}

	node_t* access(int u) {
		assert(0 <= u && u < n);
		node_t* v = &a[u];
		node_t* last = nullptr;
		for(node_t* p = v; p != nullptr; p = p->p) {
			splay(p);
			p->r = last;
			pull(p);
			last = p;
		}
		splay(v);
		return last;
	}

	void make_root(int u) {
		access(u);
		a[u].rev ^= 1;
		push(&a[u]);
	}

	void link(int u, int v) {
		make_root(v);
		a[v].p = &a[u];
	}

	void cut(int u) {
		access(u);
		if(a[u].l != nullptr) {
			a[u].l->p = nullptr;
			a[u].l = nullptr;
			pull(&a[u]);
		}
	}

	void cut(int u, int v) {
		make_root(u);
		cut(v);
	}

	bool is_connected(int u, int v) {
		if(u == v) {
			return true;
		}
		access(u), access(v);
		return a[u].p != nullptr;
	}

	int get_lca(int u, int v) {
		if(u == v) {
			return u;
		}
		access(u);
		return access(v) - &a[0];
	}

	int get_root(int u) {
		node_t* v = access(u);
		push(v);
		while(v->l != nullptr) {
			v = v->l;
			push(v);
		}
		access(v);
		return v - &a[0];
	}

	void set(int u, const S& s) {
		access(u);
		a[u].val = s;
		pull(&a[u]);
	}

	S get(int u) {
		access(u);
		return a[u].val;
	}

	void apply(int u, int v, const F& f) {
		make_root(u);
		access(v);
		all_apply(&a[v], f);
		push(&a[v]);
	}

	S prod(int u, int v) {
		make_root(u);
		access(v);
		return a[v].sum;
	}

private:
	int n;
	std::vector<node_t> a;

	void rotate(node_t* v) {
		auto attach = [&](node_t* p, bool side, node_t* c) {
			(side ? p->r : p->l) = c;
			pull(p);
			if(c != nullptr) {
				c->p = p;
			}
		};
		node_t* p = v->p;
		node_t* g = p->p;
		bool is_right = (p->r == v);
		bool is_root = p->is_root();
		attach(p, is_right, (is_right ? v->l : v->r));
		attach(v, !is_right, p);
		if(!is_root) {
			attach(g, (g->r == p), v);
		} else {
			v->p = g;
		}
	}

	void splay(node_t* v) {
		push(v);
		while(!v->is_root()) {
			auto p = v->p;
			auto g = p->p;
			if(!p->is_root()) {
				push(g);
			}
			push(p), push(v);
			if(!p->is_root()) {
				rotate((g->r == p) == (p->r == v) ? p : v);
			}
			rotate(v);
		}
	}

	void all_apply(node_t* v, F f) {
		v->val = mapping(f, v->val);
		v->sum = mapping(f, v->sum);
		v->lz = composition(f, v->lz);
	}

	void push(node_t* v) {
		if(v->lz != id()) {
			if(v->l != nullptr) {
				all_apply(v->l, v->lz);
			}
			if(v->r != nullptr) {
				all_apply(v->r, v->lz);
			}
			v->lz = id();
		}
		if(v->rev) {
			std::swap(v->l, v->r);
			if(v->l != nullptr) {
				v->l->rev ^= 1;
			}
			if(v->r != nullptr) {
				v->r->rev ^= 1;
			}
			v->sum = reversal(v->sum);
			v->rev = false;
		}
	}

	void pull(node_t* v) {
		v->sz = 1;
		v->sum = v->val;
		if(v->l != nullptr) {
			push(v->l);
			v->sum = op(v->l->sum, v->sum);
			v->sz += v->l->sz;
		}
		if(v->r != nullptr) {
			push(v->r);
			v->sum = op(v->sum, v->r->sum);
			v->sz += v->r->sz;
		}
	}
};

} // namespace felix

#line 8 "test/data-structure/lazy-lct/aoj-Do-use-segment-tree.test.cpp"
using namespace std;
using namespace felix;

struct S {
	int mx = numeric_limits<int>::min();
	int sum = 0;
	int pref = 0, suff = 0;
	int ans = 0;
	int sz = 0;
};

S e() { return S(); }

S op(S a, S b) {
	S c;
	c.mx = max(a.mx, b.mx);
	c.sum = a.sum + b.sum;
	c.pref = max(a.pref, a.sum + b.pref);
	c.suff = max(b.suff, b.sum + a.suff);
	c.ans = max({a.ans, b.ans, a.suff + b.pref});
	c.sz = a.sz + b.sz;
	return c;
}

S reversal(S s) {
	swap(s.pref, s.suff);
	return s;
}

using F = int;

F id() { return numeric_limits<int>::min(); }

S mapping(F f, S s) {
	if(f == id()) {
		return s;
	}
	s.mx = f;
	s.sum = f * s.sz;
	s.pref = s.suff = s.ans = max(f, 0) * s.sz;
	return s;
}

F composition(F a, F b) {
	if(a == id() || b == id()) {
		return a != id() ? a : b;
	}
	return a;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n, q;
	cin >> n >> q;
	vector<S> a(n);
	for(int i = 0; i < n; i++) {
		int x;
		cin >> x;
		a[i].mx = a[i].sum = x;
		a[i].ans = a[i].pref = a[i].suff = max(x, 0);
		a[i].sz = 1;
	}
	lazy_lct<S, e, op, reversal, F, id, mapping, composition> lct(a);
	for(int i = 0; i < n - 1; i++) {
		int u, v;
		cin >> u >> v;
		u--, v--;
		lct.link(u, v);
	}
	while(q--) {
		int type, u, v, w;
		cin >> type >> u >> v >> w;
		u--, v--;
		if(type == 1) {
			lct.apply(u, v, F{w});
		} else {
			S res = lct.prod(u, v);
			cout << (res.ans == 0 ? res.mx : res.ans) << "\n";
		}
	}
	return 0;
}

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