#380067 (C++14) No.898 tri-βutree

提出ソース

結果

問題	No.898 tri-βutree
ユーザー	polylogK
提出日時	2019-09-17 15:58:55
言語	C++14 (gcc 12.3.0 + boost 1.83.0)
結果	AC
実行時間	2,502 ms / 4,000 ms
コード長	7,935 bytes
コンパイル時間	3,016 ms
コンパイル使用メモリ	208,104 KB
実行使用メモリ	31,640 KB
最終ジャッジ日時	2024-11-08 21:41:34
合計ジャッジ時間	37,346 ms
ジャッジサーバーID （参考情報）	judge3 / judge5

このコードへのチャレンジ
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テストケース

テストケース表示

入力	結果	実行時間実行使用メモリ
testcase_00	AC	439 ms 31,640 KB
testcase_01	AC	2 ms 5,248 KB
testcase_02	AC	2 ms 5,248 KB
testcase_03	AC	2 ms 5,248 KB
testcase_04	AC	3 ms 5,248 KB
testcase_05	AC	2 ms 5,248 KB
testcase_06	AC	3 ms 5,248 KB
testcase_07	AC	2,046 ms 28,076 KB
testcase_08	AC	2,076 ms 28,288 KB
testcase_09	AC	2,064 ms 28,068 KB
testcase_10	AC	2,067 ms 28,148 KB
testcase_11	AC	2,084 ms 28,092 KB
testcase_12	AC	2,018 ms 28,228 KB
testcase_13	AC	2,054 ms 28,160 KB
testcase_14	AC	2,146 ms 28,160 KB
testcase_15	AC	2,041 ms 28,288 KB
testcase_16	AC	1,964 ms 28,160 KB
testcase_17	AC	1,963 ms 28,052 KB
testcase_18	AC	2,108 ms 28,076 KB
testcase_19	AC	2,073 ms 28,088 KB
testcase_20	AC	2,502 ms 28,116 KB
testcase_21	AC	2,042 ms 28,160 KB

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ソースコード

raw source code

#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = long long;
using std::cout;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

// build: you have to run it before you use
// for_each: process [l, r]
// for_each_edge: process [l, r]
// distance: returns the dist (l, r)
class heavy_light_decomposition {
	using size_type = size_t;

	using F = std::function<void (int, int)>;

	public:
	std::vector<std::vector<int>> g;
	std::vector<int> vid, inv;

	private:
	std::vector<int> head, sz, heavy, par, dep, type;

	void dfs(int root) {
		using P = std::pair<int, int>;
		
		par[root] = -1;
		dep[root] = 0;
		std::stack<P> st;
		st.push({root, 0});
		while(!st.empty()) {
			int v = st.top().first;
			int & i = st.top().second;
		
			if(i < g[v].size()) {
				int u = g[v][i++];
				if(u == par[v]) continue;
				par[u] = v;
				dep[u] = dep[v] + 1;
				st.push({u, 0});
			} else {
				st.pop();
				int tmp = 0;
				for(auto e: g[v]) {
					if(e == par[v]) continue;
					sz[v] += sz[e];
					if(tmp < sz[e]) {
						tmp = sz[e];
						heavy[v] = e;
					}
				}
			}
		}
	}
	void bfs(int root, int c, int & k) {
		std::queue<int> qu({root});
		while(!qu.empty()) {
			int h = qu.front(); qu.pop();

			for(int v = h; v != -1; v = heavy[v]) {
				type[v] = c;
				vid[v] = k++;
				inv[vid[v]] = v;
				head[v] = h;
				for(int e: g[v])
					if(e != par[v] and e != heavy[v]) qu.push(e);
			}
		}
	}

	public:
	heavy_light_decomposition() {}
	heavy_light_decomposition(int n) :
		g(n), vid(n, -1), head(n), sz(n, 1), heavy(n, -1),
		par(n), dep(n), inv(n), type(n) {}
	void add_edge(int a, int b) {
		g[a].push_back(b);
		g[b].push_back(a);
	}
	void build(std::vector<int> rs = std::vector<int>(1, 0)) {
		int c = 0, k = 0;
		for(int r: rs) {
			dfs(r);
			bfs(r, c++, k);
		}
	}
	int lca(int u, int v) {
		while(true) {
			if(vid[u] > vid[v]) std::swap(u, v);
			if(head[u] == head[v]) return u;
			v = par[head[v]];
		}
	}
	void for_each(int u, int v, const F & f) {
		while(true) {
			if(vid[u] > vid[v]) std::swap(u, v);
			f(std::max(vid[head[v]], vid[u]), vid[v]);
			if(head[u] != head[v]) v = par[head[v]];
			else break;
		}
	}
	void for_each_edge(int u, int v, const F & f) {
		while(true) {
			if(vid[u] > vid[v]) std::swap(u, v);
			if(head[u] != head[v]) {
				f(vid[head[v]], vid[v]);
				v = par[head[v]];
			} else {
				if(u != v) f(vid[u] + 1, vid[v]);
				break;
			}
		}
	}

	int distance(int u, int v) {
		return dep[u] + dep[v] - 2 * dep[lca(u, v)];
	}
};

using namespace std;
template <typename T,typename E>
struct SegmentTree{
  using F = function<T(T,T)>;
  using G = function<T(T,E)>;
  using H = function<E(E,E)>;
  int n,height;
  F f;
  G g;
  H h;
  T ti;
  E ei;
  vector<T> dat;
  vector<E> laz;
  SegmentTree(F f,G g,H h,T ti,E ei):
    f(f),g(g),h(h),ti(ti),ei(ei){}

  void init(int n_){
    n=1;height=0;
    while(n<n_) n<<=1,height++;
    dat.assign(2*n,ti);
    laz.assign(2*n,ei);
  }
  void build(const vector<T> &v){
    int n_=v.size();
    init(n_);
    for(int i=0;i<n_;i++) dat[n+i]=v[i];
    for(int i=n-1;i;i--)
      dat[i]=f(dat[(i<<1)|0],dat[(i<<1)|1]);
  }
  inline T reflect(int k){
    return laz[k]==ei?dat[k]:g(dat[k],laz[k]);
  }
  inline void eval(int k){
    if(laz[k]==ei) return;
    laz[(k<<1)|0]=h(laz[(k<<1)|0],laz[k]);
    laz[(k<<1)|1]=h(laz[(k<<1)|1],laz[k]);
    dat[k]=reflect(k);
    laz[k]=ei;
  }
  inline void thrust(int k){
    for(int i=height;i;i--) eval(k>>i);
  }
  inline void recalc(int k){
    while(k>>=1)
      dat[k]=f(reflect((k<<1)|0),reflect((k<<1)|1));
  }
  void update(int a,int b,E x){
    thrust(a+=n);
    thrust(b+=n-1);
    for(int l=a,r=b+1;l<r;l>>=1,r>>=1){
      if(l&1) laz[l]=h(laz[l],x),l++;
      if(r&1) --r,laz[r]=h(laz[r],x);
    }
    recalc(a);
    recalc(b);
  }
  void set_val(int a,T x){
    thrust(a+=n);
    dat[a]=x;laz[a]=ei;
    recalc(a);
  }
  T query(int a,int b){
    thrust(a+=n);
    thrust(b+=n-1);
    T vl=ti,vr=ti;
    for(int l=a,r=b+1;l<r;l>>=1,r>>=1) {
      if(l&1) vl=f(vl,reflect(l++));
      if(r&1) vr=f(reflect(--r),vr);
    }
    return f(vl,vr);
  }
};

struct node {
	int used;
	int depth;
	int label;
	int depth_all;
	int label_all;
	
	node() : used(1), depth(-1), label(-1), depth_all(-1), label_all(-1) {}
	node(int used, int depth, int label, int depth_all, int label_all) : used(used), depth(depth), label(label), depth_all(depth_all), label_all(label_all) {}
	void print() {
		printf("used		= %d\n", used);
		printf("depth 		= %d\n", depth);
		printf("label 		= %d\n", label);
		printf("depth_all 	= %d\n", depth_all);
		printf("label_all	= %d\n", label_all);
	}
};

int main() {
	int n; scanf("%d", &n);

	std::vector<std::vector<std::pair<int, i64>>> g(n);
	heavy_light_decomposition hld(n);
	for(int i = 0; i < n - 1; i++) {
		int a, b, c; scanf("%d%d%d", &a, &b, &c);

		g[a].push_back({b, c});
		g[b].push_back({a, c});
		hld.add_edge(a, b);
	}
	hld.build();

	std::vector<i64> dist(n), depth(n);
	auto dfs = [&](auto && dfs, int v, int par) -> void {
		for(auto e: g[v]) {
			if(e.first == par) continue;
			dist[e.first] = dist[v] + e.second;
			depth[e.first] = depth[v] + 1;
			dfs(dfs, e.first, v);
		}
	};
	dfs(dfs, 0, -1);
	
	auto calc = [dist, &hld](int u, int v) {
		return dist[u] + dist[v] - 2LL * dist[hld.lca(u, v)];
	};

	auto f = [](node a, node b) {
		node ret;
		ret.used = 0;
		if(a.depth_all > b.depth_all) {
			ret.label_all = a.label_all;
			ret.depth_all = a.depth_all;
		} else {
			ret.label_all = b.label_all;
			ret.depth_all = b.depth_all;
		}

		if(a.used and b.used) {
			ret.used = 1;
			ret.label = ret.label_all;
			ret.depth = ret.depth_all;
			return ret;
		} else if(a.used and !b.used) {
			if(a.depth_all > b.depth) {
				ret.label = a.label_all;
				ret.depth = a.depth_all;
			} else {
				ret.label = b.label;
				ret.depth = b.depth;
			}
		} else if(!a.used and b.used) {
			if(a.depth > b.depth_all) {
				ret.label = a.label;
				ret.depth = a.depth;
			} else {
				ret.label = b.label_all;
				ret.depth = b.depth_all;
			}
		} else {
			if(a.depth > b.depth) {
				ret.label = a.label;
				ret.depth = a.depth;
			} else {
				ret.label = b.label;
				ret.depth = b.depth;
			}
		}
		return ret;
	};
	auto gg = [](node a, int b) {
		if(b) {
			a.used = 1;
			a.depth = a.depth_all;
			a.label = a.label_all;
		} else {
			a.used = 0;
			a.depth = -1;
			a.label = -1;
		}
		return a;
	};
	auto h = [](int a, int b) { return b; };
	
	SegmentTree<node, int> A(f, gg, h,  node(), -1);
	A.init(n);
	for(int i = 0; i < n; i++) {
		int v = hld.inv[i];

		A.set_val(i, node(0, -1, -1, depth[v], v));
	}
	
	auto kiri = [&A](int l, int r) {
		A.update(l, r + 1, 1);
	};
	auto irik = [&A](int l, int r) {
		A.update(l, r + 1, 0);
	};

	int q; scanf("%d", &q);
	while(q--) {
		int k = 3; // scanf("%d", &k);
		std::vector<std::pair<int, int>> vec;
		for(int i = 0; i < k; i++) {
			int x; scanf("%d", &x);

			vec.push_back({depth[x], x});
		}
		sort(begin(vec), end(vec));

		if(k == 1) {
			printf("0\n");
			continue;
		}

		i64 ans = calc(vec[0].second, vec[1].second);
		int c = hld.lca(vec[0].second, vec[1].second);
		hld.for_each(vec[0].second, vec[1].second, kiri);
		for(int i = 2; i < vec.size(); i++) {
			int v = vec[i].second;
			
			node tmp = node();
			auto tanpo = [&](int l, int r) {
				tmp = f(tmp, A.query(l, r + 1));
			};
			hld.for_each(0, v, tanpo);

			if(tmp.depth == -1) {
				int u = hld.lca(v, c);
				ans += calc(u,  v) + calc(u, c);
				hld.for_each(u, v, kiri);
				hld.for_each(u, c, kiri);
				c = hld.lca(u, v);
			} else {
				int u = tmp.label;
				ans += calc(u, v);
				hld.for_each(u, v, kiri);
			}
		}

		A.update(0, n, 0);
		printf("%lld\n", ans);
	}
	return 0;
}

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結果

テストケース

ソースコード