oj.uz

Submission #555897

# Submission time Handle Problem Language Result Execution time Memory
555897 2022-05-01T18:46:29 Z blue Pipes (BOI13_pipes) C++17
74.0741 / 100
 66 ms 11648 KB 
#include <iostream>
#include <vector>
#include <queue>
#include <cassert>
using namespace std;

using ll = long long;
using vi = vector<int>;
using pii = pair<int, int>;
using vpii = vector<pii>;
using vll = vector<ll>;
#define sz(x) int(x.size())

const int mx = 100'000;

int N, M;
vpii edge[1+mx];
vll c(1+mx);


vll x(1+mx);

void dfs(int u, int p)
{
	for(pii vp : edge[u])
	{
		int v = vp.first;
		int e = vp.second;

		if(v == p) continue;
		dfs(v, u);

		x[e] = 2*c[v];

		c[u] -= c[v];
		c[v] = 0;
	}
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int N, M;
	cin >> N >> M;

	if(M > N)
	{
		cout << "0\n";
		return 0;
	}

	for(int i = 1; i <= N; i++) cin >> c[i];

	for(int j = 1; j <= M; j++)
	{
		int u, v;
		cin >> u >> v;
		edge[u].push_back({v, j});
		edge[v].push_back({u, j});
	}

	if(M == N-1)
	{
		dfs(1, 0);
	}
	else
	{
		queue<int> tbv;
		vi visit(1+N, 0);

		vi deg(1+N);
		for(int i = 1; i <= N; i++)
		{
			deg[i] = sz(edge[i]);
			if(deg[i] == 1)
			{
				tbv.push(i);
				visit[i] = 1;
			}
		}

		// cerr << "A\n";


		while(!tbv.empty())
		{
			int u = tbv.front();
			tbv.pop();

			for(auto vp : edge[u])
			{
				int v = vp.first;
				int e = vp.second;

				if(visit[v]) continue;

				deg[v]--;

				x[e] = 2*c[v];
				c[v] -= c[u];
				c[u] = 0;

				if(deg[v] == 1)
				{
					tbv.push(v);
					visit[v] = 1;
				}
			}
		}

		// cerr << "B\n";

		int U = 1;
		while(visit[U])
			U++;

		int viscount = 0;
		for(int u = 1; u <= N; u++)
			viscount += visit[u];

		vi edgevis(1+N, 0);

		// cerr << "C\n";


		vi nodes, edges;
		for(int z = 1; z <= N - viscount; z++)
		{
			for(auto vp : edge[U])
			{
				int v = vp.first;
				int e = vp.second;

				if(visit[v]) continue;
				if(edgevis[e]) continue;

				edgevis[e] = 1;


				nodes.push_back(U);
				edges.push_back(e);

				U = v;

				break;
			}
		}
		// cerr << "D\n";

		int Z = N - viscount;

		// cerr << "Z = " << Z << '\n';

		// for(int z = 0; z < Z; z++) cerr << nodes[z] << ' ' << edges[z] << '\n';

		if(Z % 2 == 0)
		{
			cout << "0\n";
			return 0;
		}

		vll a(Z), b(Z);
		a[0] = 1;
		b[0] = 0;



		for(int i = 1; i < Z; i++)
		{
			// if(!(1 <= nodes[i] && nodes[i] <= N)) while(1);
			a[i] = -a[i-1];
			b[i] = c[nodes[i]] - b[i-1]; 
		}

		// return 0;

		//(a.back() + a[0]) * x  +  (b.back() + b[0]) == c[nodes[0]]
		//x = (c[nodes[0]] - (b.back() + b[0])) / (a.back() + a[0])

		// if(a.back() + a[0] == 0) while(1);

		for(int i = 0; i < Z; i++)
		{
			x[edges[i]] = (a[i] * (c[nodes[0]] - (b.back() + b[0]))) + b[i]*2;

			assert(x[edges[i]] % 2 == 0);

			// cerr << i << " : " << nodes[i] << " : " << a[i] << ' ' << b[i] << "\n";
		}
	}

	for(int e = 1; e <= M; e++) 
		cout << x[e] << '\n';
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4180 KB Output is correct
2 Correct 2 ms 4180 KB Output is correct
3 Correct 3 ms 4180 KB Output is correct
4 Correct 63 ms 8336 KB Output is correct
5 Correct 3 ms 4180 KB Output is correct
6 Correct 2 ms 4180 KB Output is correct
7 Correct 2 ms 4180 KB Output is correct
8 Correct 2 ms 4180 KB Output is correct
9 Correct 2 ms 4180 KB Output is correct
10 Correct 3 ms 4176 KB Output is correct
11 Correct 2 ms 4180 KB Output is correct
12 Correct 3 ms 4308 KB Output is correct
13 Correct 45 ms 7480 KB Output is correct
14 Correct 48 ms 8144 KB Output is correct
15 Correct 49 ms 8336 KB Output is correct
16 Correct 42 ms 7684 KB Output is correct
17 Correct 65 ms 8316 KB Output is correct
18 Correct 54 ms 8408 KB Output is correct
19 Correct 62 ms 11648 KB Output is correct
20 Correct 2 ms 4180 KB Output is correct
21 Correct 3 ms 4180 KB Output is correct
22 Correct 66 ms 8288 KB Output is correct
23 Correct 47 ms 7544 KB Output is correct
24 Correct 62 ms 8400 KB Output is correct
25 Correct 40 ms 7708 KB Output is correct

Subtask #2
44.0740740741 / 70.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 4180 KB Output isn't correct
2 Incorrect 2 ms 4308 KB Output isn't correct
3 Correct 52 ms 9228 KB Output is correct
4 Correct 3 ms 4180 KB Output is correct
5 Correct 2 ms 4180 KB Output is correct
6 Correct 2 ms 4180 KB Output is correct
7 Incorrect 2 ms 4180 KB Output isn't correct
8 Incorrect 2 ms 4180 KB Output isn't correct
9 Correct 2 ms 4228 KB Output is correct
10 Correct 3 ms 4180 KB Output is correct
11 Correct 2 ms 4180 KB Output is correct
12 Correct 2 ms 4180 KB Output is correct
13 Correct 2 ms 4180 KB Output is correct
14 Incorrect 2 ms 4180 KB Output isn't correct
15 Incorrect 2 ms 4308 KB Output isn't correct
16 Incorrect 3 ms 4308 KB Output isn't correct
17 Correct 2 ms 4308 KB Output is correct
18 Correct 2 ms 4180 KB Output is correct
19 Correct 2 ms 4180 KB Output is correct
20 Correct 2 ms 4180 KB Output is correct
21 Correct 2 ms 4180 KB Output is correct
22 Incorrect 3 ms 4308 KB Output isn't correct
23 Incorrect 42 ms 9288 KB Output isn't correct
24 Incorrect 59 ms 10160 KB Output isn't correct
25 Correct 49 ms 9228 KB Output is correct
26 Correct 2 ms 4180 KB Output is correct
27 Correct 2 ms 4180 KB Output is correct
28 Correct 2 ms 4180 KB Output is correct
29 Correct 2 ms 4180 KB Output is correct
30 Incorrect 58 ms 9668 KB Output isn't correct
31 Incorrect 56 ms 10748 KB Output isn't correct
32 Incorrect 58 ms 9596 KB Output isn't correct
33 Correct 46 ms 9400 KB Output is correct
34 Correct 2 ms 4180 KB Output is correct
35 Correct 2 ms 4180 KB Output is correct
36 Correct 2 ms 4180 KB Output is correct
37 Correct 2 ms 4180 KB Output is correct
38 Incorrect 64 ms 9988 KB Output isn't correct
39 Incorrect 58 ms 9356 KB Output isn't correct
40 Incorrect 55 ms 10312 KB Output isn't correct
41 Correct 48 ms 9468 KB Output is correct
42 Correct 2 ms 4180 KB Output is correct
43 Correct 2 ms 4180 KB Output is correct
44 Correct 2 ms 4180 KB Output is correct
45 Correct 2 ms 4180 KB Output is correct
46 Incorrect 54 ms 9672 KB Output isn't correct
47 Incorrect 54 ms 10224 KB Output isn't correct
48 Incorrect 56 ms 10756 KB Output isn't correct
49 Correct 42 ms 9092 KB Output is correct
50 Correct 2 ms 4180 KB Output is correct
51 Correct 2 ms 4180 KB Output is correct
52 Correct 2 ms 4180 KB Output is correct
53 Correct 2 ms 4180 KB Output is correct
54 Incorrect 56 ms 9672 KB Output isn't correct