oj.uz

Submission #147259

# Submission time Handle Problem Language Result Execution time Memory
147259 2019-08-28T14:23:15 Z tincamatei Valley (BOI19_valley) C++14
100 / 100
 388 ms 30128 KB 
#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 100000;
const int MAX_Q = 100000;
const long long INF = 1LL << 60;

struct Edge {
	int a, b, cost;

	int other(int x) {
		return a ^ b ^ x;
	}
} edges[MAX_N - 1];

vector<int> graph[1+MAX_N];

int lastid;
int firstT[1+MAX_N], lastT[1+MAX_N];
long long depth[1+MAX_N], depthEuler[1+MAX_N];
bool shop[1+MAX_N], shopEuler[1+MAX_N], blockedEdge[1+MAX_N];

void predfs(int nod, int papa = -1) {
	++lastid;
	firstT[nod] = lastid;
	if(shop[nod]) {
		shopEuler[lastid] = true;
		depthEuler[lastid] = depth[nod];
	} else
		depthEuler[lastid] = INF;
	for(auto it: graph[nod]) {
		int son = edges[it].other(nod);
		int w   = edges[it].cost;

		if(son != papa) {
			depth[son] = depth[nod] + w;
			predfs(son, nod);
		}
	}
	lastT[nod] = lastid;
}

struct SegTree {
	long long aint[1+4*MAX_N], lazy[1+4*MAX_N];

	void init(int l = 1, int r = MAX_N, int nod = 1) {
		lazy[nod] = 0;
		if(l == r)
			aint[nod] = depthEuler[l];
		else if(l < r) {
			int mid = (l + r) / 2;
			init(l, mid, 2 * nod);
			init(mid + 1, r, 2 * nod + 1);
			aint[nod] = min(aint[2 * nod], aint[2 * nod + 1]);
		}
	}

	void pushLazy(int nod, int l, int r) {
		if(aint[nod] == INF)
			lazy[nod] = 0;
		else {
			aint[nod] += lazy[nod];
			if(l < r) {
				lazy[2 * nod] += lazy[nod];
				lazy[2 * nod + 1] += lazy[nod];
			}
			lazy[nod] = 0;
		}
	}

	void update(int i, int j, int val, int l = 1, int r = MAX_N, int nod = 1) {
		pushLazy(nod, l, r);
		if(j < l || r < i || j < i) return;

		if(i <= l && r <= j) {
			lazy[nod] += val;
			pushLazy(nod, l, r);
		} else {
			int mid = (l + r) / 2;
			update(i, j, val, l, mid, 2 * nod);
			update(i, j, val, mid + 1, r, 2 * nod + 1);
			aint[nod] = min(aint[2 * nod], aint[2 * nod + 1]);
		}
	}

	long long query(int i, int j, int l = 1, int r = MAX_N, int nod = 1) {
		pushLazy(nod, l, r);
		if(j < l || r < i || j < i) return INF;

		if(i <= l && r <= j)
			return aint[nod];
		else {
			int mid = (l + r) / 2;
			return min(query(i, j, l, mid, 2 * nod),
			           query(i, j, mid + 1, r, 2 * nod + 1));
		}
	}
} aint;

struct Query {
	int I;
	long long *rez;
};

vector<Query> query[1+MAX_N];
long long rez[MAX_Q];

void maindfs(int nod, int papa = 0) {
	for(auto it: query[nod]) {
		if(blockedEdge[it.I]) {
			int lowerNode;
			if(depth[edges[it.I].a] > depth[edges[it.I].b])
				lowerNode = edges[it.I].a;
			else
				lowerNode = edges[it.I].b;

			(*it.rez) = aint.query(firstT[lowerNode], lastT[lowerNode]);
		} else
			(*it.rez) = -1;
	}

	for(auto it: graph[nod]) {
		int son, w;
		son = edges[it].other(nod);
		w   = edges[it].cost;

		if(son != papa) {
			aint.update(1, MAX_N, w);
			aint.update(firstT[son], lastT[son], -2 * w);
			blockedEdge[it] = true;
			maindfs(son, nod);
			aint.update(1, MAX_N, -w);
			aint.update(firstT[son], lastT[son], 2 * w);
			blockedEdge[it] = false;
		}
	}
}

int main() {
	int N, S, Q, E;
	
	scanf("%d%d%d%d", &N, &S, &Q, &E);
	for(int i = 0; i < N - 1; ++i) {
		int a, b, w;
		scanf("%d%d%d", &a, &b, &w);
		edges[i] = {a, b, w};
		graph[a].push_back(i);
		graph[b].push_back(i);
	}

	for(int i = 0; i < S; ++i) {
		int x;
		scanf("%d", &x);
		shop[x] = true;
	}

	for(int i = 0; i < Q; ++i) {
		int I, R;
		scanf("%d%d", &I, &R);
		query[R].push_back(Query{I - 1, &rez[i]});
	}

	predfs(E);
	aint.init();
	maindfs(E);

	for(int i = 0; i < Q; ++i) {
		if(rez[i] == -1)
			printf("escaped\n");
		else if(rez[i] >= INF)//100000000000000LL)
			printf("oo\n");
		else
			printf("%lld\n", rez[i]);
	}

	return 0;
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:143:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d", &N, &S, &Q, &E);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:146:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &a, &b, &w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~
valley.cpp:154:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &x);
   ~~~~~^~~~~~~~~~
valley.cpp:160:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &I, &R);
   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 9592 KB Output is correct
2 Correct 15 ms 9592 KB Output is correct
3 Correct 15 ms 9596 KB Output is correct
4 Correct 15 ms 9592 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 9592 KB Output is correct
2 Correct 15 ms 9592 KB Output is correct
3 Correct 15 ms 9596 KB Output is correct
4 Correct 15 ms 9592 KB Output is correct
5 Correct 13 ms 9336 KB Output is correct
6 Correct 13 ms 9336 KB Output is correct
7 Correct 12 ms 9336 KB Output is correct
8 Correct 13 ms 9336 KB Output is correct
9 Correct 13 ms 9336 KB Output is correct
10 Correct 13 ms 9336 KB Output is correct
11 Correct 13 ms 9336 KB Output is correct
12 Correct 13 ms 9336 KB Output is correct
13 Correct 13 ms 9336 KB Output is correct
14 Correct 13 ms 9336 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 321 ms 24184 KB Output is correct
2 Correct 357 ms 24184 KB Output is correct
3 Correct 320 ms 23928 KB Output is correct
4 Correct 349 ms 26620 KB Output is correct
5 Correct 304 ms 26360 KB Output is correct
6 Correct 362 ms 29620 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 9592 KB Output is correct
2 Correct 15 ms 9592 KB Output is correct
3 Correct 15 ms 9596 KB Output is correct
4 Correct 15 ms 9592 KB Output is correct
5 Correct 13 ms 9336 KB Output is correct
6 Correct 13 ms 9336 KB Output is correct
7 Correct 12 ms 9336 KB Output is correct
8 Correct 13 ms 9336 KB Output is correct
9 Correct 13 ms 9336 KB Output is correct
10 Correct 13 ms 9336 KB Output is correct
11 Correct 13 ms 9336 KB Output is correct
12 Correct 13 ms 9336 KB Output is correct
13 Correct 13 ms 9336 KB Output is correct
14 Correct 13 ms 9336 KB Output is correct
15 Correct 321 ms 24184 KB Output is correct
16 Correct 357 ms 24184 KB Output is correct
17 Correct 320 ms 23928 KB Output is correct
18 Correct 349 ms 26620 KB Output is correct
19 Correct 304 ms 26360 KB Output is correct
20 Correct 362 ms 29620 KB Output is correct
21 Correct 275 ms 23560 KB Output is correct
22 Correct 296 ms 23456 KB Output is correct
23 Correct 291 ms 23272 KB Output is correct
24 Correct 317 ms 26148 KB Output is correct
25 Correct 304 ms 30096 KB Output is correct
26 Correct 309 ms 23800 KB Output is correct
27 Correct 312 ms 23544 KB Output is correct
28 Correct 302 ms 23416 KB Output is correct
29 Correct 330 ms 25352 KB Output is correct
30 Correct 329 ms 27568 KB Output is correct
31 Correct 287 ms 23800 KB Output is correct
32 Correct 307 ms 23672 KB Output is correct
33 Correct 316 ms 23688 KB Output is correct
34 Correct 388 ms 26232 KB Output is correct
35 Correct 338 ms 30128 KB Output is correct
36 Correct 314 ms 25976 KB Output is correct