Submission #995736

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
995736	2024-06-09T20:36:04 Z	MilosMilutinovic	Pipes (BOI13_pipes)	C++14	74.0741 / 100	93 ms	36556 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];
      }
    }
  }
  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	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	33 ms	8344 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	0 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	26 ms	6656 KB	Output is correct
14	Correct	31 ms	8016 KB	Output is correct
15	Correct	33 ms	8528 KB	Output is correct
16	Correct	32 ms	7288 KB	Output is correct
17	Correct	33 ms	8276 KB	Output is correct
18	Correct	34 ms	8532 KB	Output is correct
19	Correct	36 ms	12372 KB	Output is correct
20	Correct	0 ms	344 KB	Output is correct
21	Correct	0 ms	344 KB	Output is correct
22	Correct	32 ms	8540 KB	Output is correct
23	Correct	26 ms	6736 KB	Output is correct
24	Correct	39 ms	8532 KB	Output is correct
25	Correct	29 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	27 ms	9012 KB	Output is correct
4	Correct	23 ms	6836 KB	Output is correct
5	Correct	23 ms	7004 KB	Output is correct
6	Correct	90 ms	17188 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	600 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	1 ms	604 KB	Output isn't correct
17	Correct	0 ms	348 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	1 ms	348 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	1 ms	348 KB	Output is correct
22	Incorrect	0 ms	604 KB	Output isn't correct
23	Runtime error	38 ms	25176 KB	Execution killed with signal 11
24	Incorrect	38 ms	16536 KB	Output isn't correct
25	Correct	27 ms	9036 KB	Output is correct
26	Correct	24 ms	6740 KB	Output is correct
27	Correct	29 ms	6744 KB	Output is correct
28	Correct	25 ms	7000 KB	Output is correct
29	Correct	76 ms	14584 KB	Output is correct
30	Runtime error	50 ms	28588 KB	Execution killed with signal 6
31	Runtime error	50 ms	34944 KB	Execution killed with signal 6
32	Runtime error	42 ms	24080 KB	Execution killed with signal 6
33	Correct	28 ms	9428 KB	Output is correct
34	Correct	25 ms	6736 KB	Output is correct
35	Correct	23 ms	6856 KB	Output is correct
36	Correct	24 ms	6940 KB	Output is correct
37	Correct	88 ms	17216 KB	Output is correct
38	Runtime error	49 ms	32804 KB	Execution killed with signal 6
39	Runtime error	42 ms	21836 KB	Execution killed with signal 6
40	Runtime error	50 ms	28280 KB	Execution killed with signal 6
41	Correct	27 ms	9420 KB	Output is correct
42	Correct	23 ms	6492 KB	Output is correct
43	Correct	23 ms	6704 KB	Output is correct
44	Correct	24 ms	7004 KB	Output is correct
45	Correct	72 ms	14268 KB	Output is correct
46	Runtime error	53 ms	36556 KB	Execution killed with signal 6
47	Runtime error	54 ms	27848 KB	Execution killed with signal 6
48	Runtime error	49 ms	34436 KB	Execution killed with signal 6
49	Correct	26 ms	9176 KB	Output is correct
50	Correct	24 ms	6700 KB	Output is correct
51	Correct	24 ms	6948 KB	Output is correct
52	Correct	23 ms	6740 KB	Output is correct
53	Correct	93 ms	14416 KB	Output is correct
54	Runtime error	50 ms	28572 KB	Execution killed with signal 6