Submission #444004

# Submission time Handle Problem Language Result Execution time Memory
444004 2021-07-12T20:52:32 Z aryan12 Pipes (BOI13_pipes) C++17
74.0741 / 100
229 ms 29364 KB
#include <bits/stdc++.h>
using namespace std;
#define int long long

mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());

const int N = 1e5 + 5;
int change[N], result[N];
vector<pair<int, int> > g[N];
int edgeChange[N], temp[N];
bool vis[N];
int n, m, bruh;
vector<int> cycle, cycle_edges;

void dfs(int node, int par, int edgeNum) {
	for(int i = 0; i < g[node].size(); i++) {
		if(g[node][i].first != par) {
			dfs(g[node][i].first, node, g[node][i].second);
		}
	}
	int netWithParent = change[node] - result[node];
	if(par != -1) {
		result[node] += netWithParent;
		edgeChange[edgeNum] = netWithParent;
		result[par] += netWithParent;
	}
}

void Tree() {
	dfs(1, -1, -1);
	if(result[1] != change[1]) {
		cout << "0\n";
		return;
	}
	for(int i = 1; i <= m; i++) {
		cout << edgeChange[i] * 2 << "\n";
	}
}

void dfs1(int node, int par) {
	vis[node] = true;
	cycle.push_back(node);
	for(int i = 0; i < g[node].size(); i++) {
		if(g[node][i].first == par) {
			continue;
		}
		if(!vis[g[node][i].first]) {
			cycle_edges.push_back(g[node][i].second);
			dfs1(g[node][i].first, node);
		}
		if(g[node][i].first == bruh) {
			cycle_edges.push_back(g[node][i].second);
		}
	}
}

void Solve() {
	cin >> n >> m;
	for(int i = 1; i <= n; i++) {
		cin >> change[i];
	}
	for(int i = 1; i <= m; i++) {
		int u, v;
		cin >> u >> v;
		g[u].push_back(make_pair(v, i));
		g[v].push_back(make_pair(u, i));
	}
	if(m == n - 1) {
		Tree();
		return;
	}
	if(m > n) {
		cout << "0\n";
		return;
	}
	int cnt = 0;
	queue<int> q;
	for(int i = 1; i <= n; i++) {
		vis[i] = false;
		temp[i] = g[i].size();
		if(temp[i] == 1) {
			q.push(i);
		}
	}
	while(!q.empty()) {
		int node = q.front();
		vis[node] = true;
		q.pop();
		cnt++;
		for(int i = 0; i < g[node].size(); i++) {
			if(!vis[g[node][i].first]) {
				temp[g[node][i].first]--;
				if(temp[g[node][i].first] == 1) {
					q.push(g[node][i].first);
				}
				int netChange = change[node] - result[node];
				edgeChange[g[node][i].second] = netChange;
				result[node] += netChange;
				result[g[node][i].first] += netChange;
			}
		}
	}
	if((n - cnt) % 2 == 0) {
		cout << "0\n";
		return;
	}
	for(int i = 1; i <= n; i++) {
		if(!vis[i]) {
			bruh = i;
			dfs1(i, -1);
		}
	}
	/*for(int i = 1; i <= n; i++) {
		cout << "change[i] = " << change[i] << ", result[i] = " << result[i] << "\n";
	}*/
	int sum = 0;
	for(int i = 0; i < cycle.size(); i++) {
		if(i % 2 == 1) {
			sum += (change[cycle[i]] - result[cycle[i]]);
		}
		else {
			sum -= (change[cycle[i]] - result[cycle[i]]);
		}
	}
	if(sum % 2 == 1) {
		cout << "0\n";
		return;
	}
	//cout << "sum = " << sum << "\n";
	edgeChange[cycle_edges[cycle_edges.size() - 1]] = sum / 2;
	edgeChange[cycle_edges[0]] = change[cycle[0]] - result[cycle[0]] - edgeChange[cycle_edges[cycle_edges.size() - 1]];
	/*for(int i = 0; i < cycle_edges.size(); i++) {
		cout << cycle_edges[i] << " ";
	}
	cout << "\n";
	for(int i = 0; i < cycle.size(); i++) {
		cout << cycle[i] << " ";
	}
	cout << "\n";*/
	for(int i = 1; i < cycle_edges.size() - 1; i++) {
		edgeChange[cycle_edges[i]] = change[cycle[i]] - result[cycle[i]] - edgeChange[cycle_edges[i - 1]];
	}
	for(int i = 1; i <= m; i++) {
		cout << edgeChange[i] * 2 << "\n";
	}
}

int32_t main() {
	auto begin = std::chrono::high_resolution_clock::now();
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int t = 1;
	//cin >> t;
	while(t--) {
		Solve();
	}
	auto end = std::chrono::high_resolution_clock::now();
    auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
    cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n"; 
	return 0;
}

Compilation message

pipes.cpp: In function 'void dfs(long long int, long long int, long long int)':
pipes.cpp:16:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |  for(int i = 0; i < g[node].size(); i++) {
      |                 ~~^~~~~~~~~~~~~~~~
pipes.cpp: In function 'void dfs1(long long int, long long int)':
pipes.cpp:43:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for(int i = 0; i < g[node].size(); i++) {
      |                 ~~^~~~~~~~~~~~~~~~
pipes.cpp: In function 'void Solve()':
pipes.cpp:90:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   90 |   for(int i = 0; i < g[node].size(); i++) {
      |                  ~~^~~~~~~~~~~~~~~~
pipes.cpp:117:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  117 |  for(int i = 0; i < cycle.size(); i++) {
      |                 ~~^~~~~~~~~~~~~~
pipes.cpp:140:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  140 |  for(int i = 1; i < cycle_edges.size() - 1; i++) {
      |                 ~~^~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 2636 KB Output is correct
2 Correct 2 ms 2636 KB Output is correct
3 Correct 2 ms 2764 KB Output is correct
4 Correct 75 ms 10432 KB Output is correct
5 Correct 2 ms 2636 KB Output is correct
6 Correct 2 ms 2636 KB Output is correct
7 Correct 2 ms 2636 KB Output is correct
8 Correct 2 ms 2648 KB Output is correct
9 Correct 2 ms 2636 KB Output is correct
10 Correct 2 ms 2764 KB Output is correct
11 Correct 2 ms 2764 KB Output is correct
12 Correct 3 ms 2764 KB Output is correct
13 Correct 54 ms 8872 KB Output is correct
14 Correct 67 ms 10084 KB Output is correct
15 Correct 74 ms 10516 KB Output is correct
16 Correct 57 ms 9296 KB Output is correct
17 Correct 71 ms 10476 KB Output is correct
18 Correct 68 ms 10564 KB Output is correct
19 Correct 81 ms 13604 KB Output is correct
20 Correct 2 ms 2636 KB Output is correct
21 Correct 2 ms 2764 KB Output is correct
22 Correct 74 ms 10632 KB Output is correct
23 Correct 52 ms 8892 KB Output is correct
24 Correct 72 ms 10576 KB Output is correct
25 Correct 56 ms 9256 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 2636 KB Output isn't correct
2 Incorrect 2 ms 2764 KB Output isn't correct
3 Correct 52 ms 10760 KB Output is correct
4 Correct 48 ms 8592 KB Output is correct
5 Correct 53 ms 8380 KB Output is correct
6 Correct 214 ms 29300 KB Output is correct
7 Incorrect 2 ms 2636 KB Output isn't correct
8 Incorrect 2 ms 2636 KB Output isn't correct
9 Correct 2 ms 2636 KB Output is correct
10 Correct 2 ms 2636 KB Output is correct
11 Correct 2 ms 2636 KB Output is correct
12 Correct 2 ms 2636 KB Output is correct
13 Correct 2 ms 2636 KB Output is correct
14 Incorrect 2 ms 2636 KB Output isn't correct
15 Incorrect 2 ms 2764 KB Output isn't correct
16 Incorrect 2 ms 2764 KB Output isn't correct
17 Correct 3 ms 2764 KB Output is correct
18 Correct 2 ms 2636 KB Output is correct
19 Correct 2 ms 2636 KB Output is correct
20 Correct 2 ms 2636 KB Output is correct
21 Correct 3 ms 2764 KB Output is correct
22 Incorrect 2 ms 2764 KB Output isn't correct
23 Incorrect 69 ms 14936 KB Output isn't correct
24 Incorrect 93 ms 16716 KB Output isn't correct
25 Correct 61 ms 10784 KB Output is correct
26 Correct 55 ms 8644 KB Output is correct
27 Correct 49 ms 8516 KB Output is correct
28 Correct 62 ms 8800 KB Output is correct
29 Correct 183 ms 24088 KB Output is correct
30 Incorrect 80 ms 15652 KB Output isn't correct
31 Incorrect 88 ms 19816 KB Output isn't correct
32 Incorrect 79 ms 13296 KB Output isn't correct
33 Correct 57 ms 11204 KB Output is correct
34 Correct 48 ms 8644 KB Output is correct
35 Correct 49 ms 8552 KB Output is correct
36 Correct 63 ms 8684 KB Output is correct
37 Correct 229 ms 29364 KB Output is correct
38 Incorrect 82 ms 16124 KB Output isn't correct
39 Incorrect 82 ms 12712 KB Output isn't correct
40 Incorrect 88 ms 16352 KB Output isn't correct
41 Correct 55 ms 11008 KB Output is correct
42 Correct 48 ms 8468 KB Output is correct
43 Correct 53 ms 8504 KB Output is correct
44 Correct 47 ms 8336 KB Output is correct
45 Correct 164 ms 26692 KB Output is correct
46 Incorrect 82 ms 15544 KB Output isn't correct
47 Incorrect 84 ms 16440 KB Output isn't correct
48 Incorrect 83 ms 19604 KB Output isn't correct
49 Correct 58 ms 10820 KB Output is correct
50 Correct 55 ms 8644 KB Output is correct
51 Correct 52 ms 8636 KB Output is correct
52 Correct 53 ms 8540 KB Output is correct
53 Correct 174 ms 26052 KB Output is correct
54 Incorrect 80 ms 15032 KB Output isn't correct