Submission #995734

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
995734	2024-06-09T20:34:00 Z	MilosMilutinovic	Pipes (BOI13_pipes)	C++14	74.0741 / 100	92 ms	36616 KB

pipes

#include <bits/stdc++.h>

using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  vector<long long> a(n);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  vector<vector<array<int, 2>>> g(n);
  for (int i = 0; i < m; i++) {
    int x, y;
    cin >> x >> y;
    --x; --y;
    g[x].push_back({y, i});
    g[y].push_back({x, i});
  }
  if (m > n) {
    cout << 0 << '\n';
    return 0;
  }
  if (n == 1) {
    cout << 2 * a[0] << '\n';
    return 0;
  }
  if (m < n) {
    vector<long long> res(m);
    function<void(int, int)> Dfs = [&](int v, int pv) {
      for (auto& e : g[v]) {
        int u = e[0];
        if (u == pv) {
          continue;
        }
        Dfs(u, v);
        if (a[u] != 0) {
          res[e[1]] = 2 * a[u];
          a[v] -= a[u];
        }
      }
    };
    Dfs(0, 0);
    if (a[0] != 0) {
      cout << 0 << '\n';
      return 0;
    }
    for (int i = 0; i < m; i++) {
      cout << res[i] << '\n';
    }
    return 0;
  }
  vector<int> deg(n);
  for (int i = 0; i < n; i++) {
    deg[i] = (int) g[i].size();
  }
  vector<int> que;
  for (int i = 0; i < n; i++) {
    if (deg[i] == 1) {
      que.push_back(i);
    }
  }
  auto orig = a;
  vector<long long> res(m);
  for (int b = 0; b < (int) que.size(); b++) {
    int i = que[b];
    for (auto& e : g[i]) {
      int j = e[0];
      deg[j] -= 1;
      if (deg[j] == 1) {
        que.push_back(j);
        res[e[1]] = 2 * a[i];
        a[j] -= a[i];
      }
    }
  }
  a = orig;
  vector<int> cyc;
  for (int i = 0; i < n; i++) {
    if (deg[i] > 1) {
      cyc.push_back(i);
    }
  }
  if ((int) cyc.size() % 2 == 0) {
    cout << 0 << '\n';
    return 0;
  }
  vector<bool> was(n);
  vector<long long> vals;
  vector<int> ids;
  function<void(int)> Dfs = [&](int v) {
    was[v] = true;
    vals.push_back(a[v]);
    int back = -1;
    bool found = false;
    for (auto& e : g[v]) {
      int u = e[0];
      int i = e[1];
      if (u == cyc[0]) {
        back = i;
      }
      if (was[u]) {
        continue;
      }
      found = true;
      ids.push_back(i);
      Dfs(u);
    }
    if (!found) {
      ids.push_back(back);
    }
  }; 
  Dfs(cyc[0]);
  long long total = 0;
  for (int i = 0; i < (int) vals.size(); i++) {
    total = vals[i] - total;
  }
  res[ids.back()] = 2 * total;
  for (int i = 0; i < n; i++) {
    for (auto& p : g[i]) {
      if (p[2] == ids.back()) {
        a[i] -= total;
      }
    }
  }
  was = vector<bool>(n, false);
  Dfs = [&](int v) {
    was[v] = true;
    for (auto& p : g[v]) {
      int u = p[0];
      int i = p[1];
      if (deg[u] <= 1 || was[u]) {
        continue;
      }
      Dfs(u);
      res[i] = 2 * a[u];
      a[v] -= a[u];
    }
  };
  Dfs(cyc.back());
  if (a != vector<long long>(n, 0LL)) {
    cout << 0 << '\n';
    return 0;
  }
  for (int i = 0; i < m; i++) {
    cout << res[i] << '\n';
  }
  return 0;
}

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	348 KB	Output is correct
2	Correct	1 ms	348 KB	Output is correct
3	Correct	1 ms	348 KB	Output is correct
4	Correct	33 ms	8304 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	0 ms	348 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	1 ms	348 KB	Output is correct
11	Correct	0 ms	348 KB	Output is correct
12	Correct	1 ms	348 KB	Output is correct
13	Correct	32 ms	6748 KB	Output is correct
14	Correct	42 ms	8016 KB	Output is correct
15	Correct	33 ms	8536 KB	Output is correct
16	Correct	29 ms	7252 KB	Output is correct
17	Correct	32 ms	8272 KB	Output is correct
18	Correct	32 ms	8528 KB	Output is correct
19	Correct	36 ms	12380 KB	Output is correct
20	Correct	0 ms	344 KB	Output is correct
21	Correct	0 ms	344 KB	Output is correct
22	Correct	33 ms	8460 KB	Output is correct
23	Correct	26 ms	6748 KB	Output is correct
24	Correct	34 ms	8532 KB	Output is correct
25	Correct	34 ms	6992 KB	Output is correct

Subtask #2

44.0740740741 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Runtime error	1 ms	604 KB	Execution killed with signal 6
2	Runtime error	1 ms	860 KB	Execution killed with signal 6
3	Correct	26 ms	9048 KB	Output is correct
4	Correct	23 ms	6744 KB	Output is correct
5	Correct	25 ms	7004 KB	Output is correct
6	Correct	92 ms	17268 KB	Output is correct
7	Runtime error	1 ms	604 KB	Execution killed with signal 6
8	Incorrect	0 ms	348 KB	Output isn't correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	348 KB	Output is correct
11	Correct	0 ms	348 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Runtime error	1 ms	604 KB	Execution killed with signal 6
15	Runtime error	1 ms	860 KB	Execution killed with signal 6
16	Incorrect	0 ms	348 KB	Output isn't correct
17	Correct	1 ms	348 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	0 ms	348 KB	Output is correct
20	Correct	1 ms	344 KB	Output is correct
21	Correct	1 ms	348 KB	Output is correct
22	Incorrect	1 ms	604 KB	Output isn't correct
23	Runtime error	41 ms	25036 KB	Execution killed with signal 11
24	Incorrect	39 ms	16456 KB	Output isn't correct
25	Correct	25 ms	9048 KB	Output is correct
26	Correct	25 ms	6756 KB	Output is correct
27	Correct	28 ms	6536 KB	Output is correct
28	Correct	28 ms	7004 KB	Output is correct
29	Correct	92 ms	14812 KB	Output is correct
30	Runtime error	50 ms	28584 KB	Execution killed with signal 6
31	Runtime error	50 ms	34960 KB	Execution killed with signal 11
32	Runtime error	42 ms	24048 KB	Execution killed with signal 6
33	Correct	30 ms	9428 KB	Output is correct
34	Correct	27 ms	6736 KB	Output is correct
35	Correct	23 ms	6820 KB	Output is correct
36	Correct	26 ms	7000 KB	Output is correct
37	Correct	91 ms	17180 KB	Output is correct
38	Runtime error	52 ms	32780 KB	Execution killed with signal 6
39	Runtime error	41 ms	21844 KB	Execution killed with signal 6
40	Runtime error	47 ms	28276 KB	Execution killed with signal 6
41	Correct	25 ms	9432 KB	Output is correct
42	Correct	23 ms	6748 KB	Output is correct
43	Correct	23 ms	6740 KB	Output is correct
44	Correct	23 ms	6992 KB	Output is correct
45	Correct	74 ms	14220 KB	Output is correct
46	Runtime error	54 ms	36616 KB	Execution killed with signal 11
47	Runtime error	46 ms	27896 KB	Execution killed with signal 6
48	Runtime error	53 ms	34432 KB	Execution killed with signal 6
49	Correct	26 ms	9172 KB	Output is correct
50	Correct	24 ms	6868 KB	Output is correct
51	Correct	23 ms	6996 KB	Output is correct
52	Correct	26 ms	6744 KB	Output is correct
53	Correct	81 ms	14420 KB	Output is correct
54	Runtime error	48 ms	28568 KB	Execution killed with signal 6