답안 #85892 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
85892	2018-11-22T14:53:24 Z	fasterthanyou	Pipes (BOI13_pipes)	C++14	100 / 100	254 ms	18872 KB

pipes

#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#include <map>
using namespace std;
 
int n, m, child[100015], tmp[100015];
long long d[100015], res[500015];
vector<pair<int, int> > g[100015];
pair<int, int> p[100015];
queue<int> q;

int color[100015], cycleStart, cycleEnd;
bool flag = 0, inCycle[100015];
pair<int, int> par[100015];
vector<int> Ncycle;

void findcycle (int u, int pv)
{
	color[u] = 1;
	for (int i = 0; i < (int)g[u].size(); ++i)
	{
		if (flag) return;
		int v = g[u][i].first;
		if (color[v] == 0)
		{
			findcycle(v, u);
			par[v] = {u, g[u][i].second};
		}
		else if (color[v] == 1 && v != pv)
		{
			cycleStart = v;
			cycleEnd = u;
			flag = 1;
			return;
		}
	}
	color[u] = 2;
}

void dfsx (int u, int pv)
{
	child[u] = 0;
	for (int i = 0; i < (int)g[u].size(); ++i)
	{
		int v = g[u][i].first;
		if (v == pv || inCycle[v]) continue;
		dfsx(v, u);
		child[u] += child[v] + 1;
		p[v] = {u, g[u][i].second};
	}
}

void caseCycle()
{
	findcycle(1, -1);
	int tEnd = cycleEnd;
	while (cycleEnd != cycleStart)
	{
		inCycle[cycleEnd] = 1;
		Ncycle.push_back(cycleEnd);
		cycleEnd = par[cycleEnd].first;
	}
	inCycle[cycleStart] = 1;
	Ncycle.push_back(cycleStart);

	if ((int)Ncycle.size() % 2 == 0)
	{
		cout << 0;
		return;
	}

	for (int i = 0; i < (int)Ncycle.size(); ++i)
		dfsx(Ncycle[i], -1);

	for (int i = 1; i <= n; ++i)
		tmp[i] = child[i];

	for (int i = 1; i <= n; ++i)
		if (child[i] == 0 && !inCycle[i]) q.push(i);

	while (!q.empty())
	{
		int u = q.front(); q.pop();
		d[p[u].first] -= d[u];
		child[p[u].first] -= (tmp[u] + 1);
 
		res[p[u].second] = d[u];
		if (child[p[u].first] < 1 && !inCycle[p[u].first]) q.push(p[u].first);		
	}
	

	long long sum = 0;
	for (int i = 0; i < (int)Ncycle.size(); ++i)
		sum += d[Ncycle[i]] * (i & 1 ? -1 : 1);
	sum /= 2;
	for (int i = 0; i < (int)g[cycleStart].size(); ++i)
		if (g[cycleStart][i].first == tEnd)
		{
			res[g[cycleStart][i].second] = sum;
			d[cycleStart] -= sum;
			d[tEnd] -= sum;
			break;
		}
	while (tEnd != cycleStart)
	{
		res[par[tEnd].second] = d[tEnd];
		d[par[tEnd].first] -= d[tEnd];
		tEnd = par[tEnd].first;
	}
	for (int id = 1; id <= m; ++id)
		cout << res[id] << '\n';
}

void dfs (int u, int pv)
{
	child[u] = 0;
	for (int i = 0; i < (int)g[u].size(); ++i)
	{
		int v = g[u][i].first;
		if (v == pv) continue;
 
		dfs(v, u);
		child[u] += child[v] + 1;
		p[v] = {u, g[u][i].second};
	}
}
 
void caseTree()
{
	p[1] = {-1, -1};
	dfs(1, -1);
 
	for (int i = 2; i <= n; ++i)
		if (child[i] == 0) q.push(i);	
	for (int i = 1; i <= n; ++i)
		tmp[i] = child[i];
 
	while (!q.empty())
	{
		int u = q.front(); q.pop();
		d[p[u].first] -= d[u];
		child[p[u].first] -= (tmp[u] + 1);
 
		if (p[u].first != -1) res[p[u].second] = d[u];
		if (child[p[u].first] < 1 && p[u].first != -1) q.push(p[u].first);
	}
	for (int id = 1; id <= m; ++id)
		cout << res[id] << '\n';
}
 
int main()
{
	ios_base::sync_with_stdio(false); cin.tie(NULL);
	//freopen("pipes.inp", "r", stdin);
	//freopen("pipes.out", "w", stdout);
 
	cin >> n >> m;
	for (int i = 1; i <= n; ++i)
		cin >> d[i],
		d[i] *= 2;
	for (int i = 0, u, v; i < m; ++i)
	{
		cin >> u >> v;
		g[u].push_back({v, i + 1});
		g[v].push_back({u, i + 1});
 	}
	if (m == n - 1) 
		caseTree();
	else if (m == n)
		caseCycle();
	else
		cout << 0;
}

Subtask #1
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	2680 KB	Output is correct
2	Correct	4 ms	2812 KB	Output is correct
3	Correct	4 ms	2872 KB	Output is correct
4	Correct	86 ms	10312 KB	Output is correct
5	Correct	5 ms	10312 KB	Output is correct
6	Correct	5 ms	10312 KB	Output is correct
7	Correct	4 ms	10312 KB	Output is correct
8	Correct	4 ms	10312 KB	Output is correct
9	Correct	5 ms	10312 KB	Output is correct
10	Correct	4 ms	10312 KB	Output is correct
11	Correct	5 ms	10312 KB	Output is correct
12	Correct	5 ms	10312 KB	Output is correct
13	Correct	68 ms	10312 KB	Output is correct
14	Correct	82 ms	10312 KB	Output is correct
15	Correct	87 ms	10404 KB	Output is correct
16	Correct	71 ms	10404 KB	Output is correct
17	Correct	89 ms	10416 KB	Output is correct
18	Correct	94 ms	10512 KB	Output is correct
19	Correct	78 ms	13612 KB	Output is correct
20	Correct	5 ms	13612 KB	Output is correct
21	Correct	5 ms	13612 KB	Output is correct
22	Correct	123 ms	13612 KB	Output is correct
23	Correct	57 ms	13612 KB	Output is correct
24	Correct	78 ms	13612 KB	Output is correct
25	Correct	67 ms	13612 KB	Output is correct

Subtask #2
70.0 / 70.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	13612 KB	Output is correct
2	Correct	4 ms	13612 KB	Output is correct
3	Correct	66 ms	13612 KB	Output is correct
4	Correct	67 ms	13612 KB	Output is correct
5	Correct	61 ms	13612 KB	Output is correct
6	Correct	227 ms	17596 KB	Output is correct
7	Correct	4 ms	17596 KB	Output is correct
8	Correct	5 ms	17596 KB	Output is correct
9	Correct	4 ms	17596 KB	Output is correct
10	Correct	4 ms	17596 KB	Output is correct
11	Correct	4 ms	17596 KB	Output is correct
12	Correct	4 ms	17596 KB	Output is correct
13	Correct	4 ms	17596 KB	Output is correct
14	Correct	4 ms	17596 KB	Output is correct
15	Correct	5 ms	17596 KB	Output is correct
16	Correct	5 ms	17596 KB	Output is correct
17	Correct	4 ms	17596 KB	Output is correct
18	Correct	4 ms	17596 KB	Output is correct
19	Correct	4 ms	17596 KB	Output is correct
20	Correct	4 ms	17596 KB	Output is correct
21	Correct	5 ms	17596 KB	Output is correct
22	Correct	5 ms	17596 KB	Output is correct
23	Correct	68 ms	17596 KB	Output is correct
24	Correct	87 ms	17596 KB	Output is correct
25	Correct	88 ms	17596 KB	Output is correct
26	Correct	55 ms	17596 KB	Output is correct
27	Correct	60 ms	17596 KB	Output is correct
28	Correct	101 ms	17596 KB	Output is correct
29	Correct	207 ms	17596 KB	Output is correct
30	Correct	134 ms	18108 KB	Output is correct
31	Correct	92 ms	18356 KB	Output is correct
32	Correct	86 ms	18356 KB	Output is correct
33	Correct	73 ms	18356 KB	Output is correct
34	Correct	59 ms	18356 KB	Output is correct
35	Correct	54 ms	18356 KB	Output is correct
36	Correct	56 ms	18356 KB	Output is correct
37	Correct	254 ms	18356 KB	Output is correct
38	Correct	94 ms	18356 KB	Output is correct
39	Correct	85 ms	18356 KB	Output is correct
40	Correct	88 ms	18356 KB	Output is correct
41	Correct	75 ms	18356 KB	Output is correct
42	Correct	66 ms	18356 KB	Output is correct
43	Correct	55 ms	18356 KB	Output is correct
44	Correct	60 ms	18356 KB	Output is correct
45	Correct	197 ms	18356 KB	Output is correct
46	Correct	110 ms	18872 KB	Output is correct
47	Correct	99 ms	18872 KB	Output is correct
48	Correct	116 ms	18872 KB	Output is correct
49	Correct	62 ms	18872 KB	Output is correct
50	Correct	56 ms	18872 KB	Output is correct
51	Correct	54 ms	18872 KB	Output is correct
52	Correct	53 ms	18872 KB	Output is correct
53	Correct	242 ms	18872 KB	Output is correct
54	Correct	107 ms	18872 KB	Output is correct

답안 #85892

Compilation message

Subtask #1 30.0 / 30.0

Subtask #2 70.0 / 70.0

Subtask #1
30.0 / 30.0

Subtask #2
70.0 / 70.0