oj.uz

Submission #443791

# Submission time Handle Problem Language Result Execution time Memory
443791 2021-07-12T06:21:12 Z wind_reaper Pipes (BOI13_pipes) C++17
74.0741 / 100
 524 ms 131076 KB 
#include <bits/stdc++.h>

using namespace std;

const int MXN = 100000;

set<array<int, 2>> g[MXN];
int change[MXN];
vector<bool> vis(MXN);

void solve(){
	int N, M;
	cin >> N >> M;

	for(int i = 0; i < N; i++)
		cin >> change[i];

	for(int i = 0; i < M; i++){
		int u, v;
		cin >> u >> v;
		--u, --v;
		g[u].insert({v, i});
		g[v].insert({u, i});
	}

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

	queue<array<int, 3>> q;
	for(int i = 0; i < N; i++)
		if(g[i].size() < 2){
			q.push({i, (*g[i].begin())[0], (*g[i].begin())[1]});
			vis[i] = 1;
		}

	int cnt = 0;

	vector<int> ans(M);

	while(!q.empty()){
		auto [u, par, idx] = q.front();
		q.pop();

		++cnt;

		int t = change[u];
		ans[idx] += 2*t;
		change[u] -= t;
		change[par] -= t;

		g[par].erase({u, idx});

		if(g[par].size() == 1 && !vis[par])
			q.push({par, (*g[par].begin())[0], (*g[par].begin())[1]});
	}

	if(cnt < N){
		if(!((N - cnt) & 1)){
			cout << 0 << '\n';
			return;
		}

		int x;
		for(int i = 0; i < N; i++) 
			if(!vis[i]) 
				x = i;

		int u = x;

		vector<int> a, b;

		while(u != x || a.empty()){
			auto [v, idx] = a.empty() || (*g[u].begin())[0] != a.back() ? *g[u].begin() : *g[u].rbegin();
			a.push_back(v);
			b.push_back(idx);
			u = v;
		}

		N = a.size();
		vector<int> suf(N);
		suf[N-1] = change[a[N-1]];
		for(int i = N - 2; i >= 0; --i)
			suf[i] = change[a[i]] - suf[i+1];
		int pre = 0;

		for(int i = 0; i < N; i++){
			pre = change[a[i]] - pre;
			ans[b[i]] = (pre + (i + 1 < N ? suf[i+1] : 0));
		}
	}

	for(int i = 0; i < M; i++)
		cout << ans[i] << '\n';
}

int32_t main(){
	ios_base::sync_with_stdio(false); 
	cin.tie(NULL); 

	solve();

	return 0; 
}

Compilation message

pipes.cpp: In function 'void solve()':
pipes.cpp:74:16: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   74 |   while(u != x || a.empty()){
      |         ~~~~~~~^~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4940 KB Output is correct
2 Correct 4 ms 5068 KB Output is correct
3 Correct 4 ms 5068 KB Output is correct
4 Correct 122 ms 17732 KB Output is correct
5 Correct 3 ms 4940 KB Output is correct
6 Correct 3 ms 5032 KB Output is correct
7 Correct 3 ms 5028 KB Output is correct
8 Correct 3 ms 4940 KB Output is correct
9 Correct 4 ms 5032 KB Output is correct
10 Correct 5 ms 5068 KB Output is correct
11 Correct 4 ms 5068 KB Output is correct
12 Correct 4 ms 5068 KB Output is correct
13 Correct 101 ms 15144 KB Output is correct
14 Correct 105 ms 16964 KB Output is correct
15 Correct 118 ms 17816 KB Output is correct
16 Correct 101 ms 15872 KB Output is correct
17 Correct 139 ms 17708 KB Output is correct
18 Correct 115 ms 17768 KB Output is correct
19 Correct 97 ms 17164 KB Output is correct
20 Correct 3 ms 4940 KB Output is correct
21 Correct 4 ms 5036 KB Output is correct
22 Correct 129 ms 17756 KB Output is correct
23 Correct 88 ms 15140 KB Output is correct
24 Correct 155 ms 17816 KB Output is correct
25 Correct 103 ms 15568 KB Output is correct

Subtask #2
44.0740740741 / 70.0

# Verdict Execution time Memory Grader output
1 Runtime error 259 ms 131076 KB Execution killed with signal 9
2 Runtime error 263 ms 131076 KB Execution killed with signal 9
3 Correct 91 ms 16496 KB Output is correct
4 Correct 92 ms 16276 KB Output is correct
5 Correct 75 ms 16032 KB Output is correct
6 Correct 483 ms 58564 KB Output is correct
7 Runtime error 286 ms 131076 KB Execution killed with signal 9
8 Runtime error 269 ms 131076 KB Execution killed with signal 9
9 Correct 3 ms 4940 KB Output is correct
10 Correct 3 ms 4940 KB Output is correct
11 Correct 3 ms 5024 KB Output is correct
12 Correct 4 ms 4940 KB Output is correct
13 Correct 3 ms 4976 KB Output is correct
14 Runtime error 261 ms 131076 KB Execution killed with signal 9
15 Runtime error 258 ms 131076 KB Execution killed with signal 9
16 Runtime error 259 ms 131076 KB Execution killed with signal 9
17 Correct 4 ms 5068 KB Output is correct
18 Correct 4 ms 5068 KB Output is correct
19 Correct 4 ms 5068 KB Output is correct
20 Correct 4 ms 5068 KB Output is correct
21 Correct 5 ms 5324 KB Output is correct
22 Runtime error 273 ms 131076 KB Execution killed with signal 9
23 Runtime error 325 ms 131076 KB Execution killed with signal 9
24 Runtime error 321 ms 131076 KB Execution killed with signal 9
25 Correct 90 ms 16344 KB Output is correct
26 Correct 75 ms 16276 KB Output is correct
27 Correct 70 ms 16176 KB Output is correct
28 Correct 76 ms 16972 KB Output is correct
29 Correct 407 ms 47964 KB Output is correct
30 Runtime error 323 ms 131076 KB Execution killed with signal 9
31 Runtime error 304 ms 131076 KB Execution killed with signal 9
32 Runtime error 341 ms 131076 KB Execution killed with signal 9
33 Correct 92 ms 16952 KB Output is correct
34 Correct 67 ms 16320 KB Output is correct
35 Correct 70 ms 16344 KB Output is correct
36 Correct 72 ms 16472 KB Output is correct
37 Correct 506 ms 58596 KB Output is correct
38 Runtime error 322 ms 131076 KB Execution killed with signal 9
39 Runtime error 346 ms 131076 KB Execution killed with signal 9
40 Runtime error 317 ms 131076 KB Execution killed with signal 9
41 Correct 85 ms 16732 KB Output is correct
42 Correct 68 ms 16476 KB Output is correct
43 Correct 75 ms 16364 KB Output is correct
44 Correct 72 ms 16076 KB Output is correct
45 Correct 524 ms 52188 KB Output is correct
46 Runtime error 317 ms 131076 KB Execution killed with signal 9
47 Runtime error 343 ms 131076 KB Execution killed with signal 9
48 Runtime error 324 ms 131076 KB Execution killed with signal 9
49 Correct 95 ms 16536 KB Output is correct
50 Correct 69 ms 16276 KB Output is correct
51 Correct 88 ms 16300 KB Output is correct
52 Correct 69 ms 16132 KB Output is correct
53 Correct 461 ms 53124 KB Output is correct
54 Runtime error 343 ms 131076 KB Execution killed with signal 9