oj.uz

Submission #677836

# Submission time Handle Problem Language Result Execution time Memory
677836 2023-01-04T12:26:33 Z dooompy Pipes (BOI13_pipes) C++17
74.0741 / 100
 121 ms 18380 KB 
#include "bits/stdc++.h"

using namespace std;

void abc() {cout << endl;}
template <typename T, typename ...U> void abc(T a, U ...b) {
    cout << a << ' ', abc(b...);
}
template <typename T> void printv(T l, T r) {
    while (l != r) cout << *l << " \n"[++l == r];
}
template <typename A, typename B> istream& operator >> (istream& o, pair<A, B> &a) {
    return o >> a.first >> a.second;
}
template <typename A, typename B> ostream& operator << (ostream& o, pair<A, B> a) {
    return o << '(' << a.first << ", " << a.second << ')';
}
template <typename T> ostream& operator << (ostream& o, vector<T> a) {
    bool is = false;
    for (T i : a) {o << (is ? ' ' : '{'), is = true, o << i;}
    return o << '}';
}

#ifdef local
#define test(args...) abc("[" + string(#args) + "]", args)
#else
#define test(args...) void(0)
#endif

using ll = long long;

ll v[100005];

set<int> adj[100005];
ll calc[500005];
int en[500005], out[500005];

bool seen[100005];

bool seen2[100005];
vector<pair<int, int>> ord;

void dfs(int cur, int p, int root) {

    int idx = *adj[cur].begin();

    int nxtidx = (en[idx] == cur ? out[idx] : en[idx]);

    if (nxtidx == p) {
        idx = *adj[cur].rbegin();

        nxtidx = (en[idx] == cur ? out[idx] : en[idx]);
    }

    ord.push_back({cur, idx});

    if (nxtidx != root) dfs(nxtidx, cur, root);
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
//    freopen("test.txt", "r", stdin);
//    freopen("", "w", stdout);
    int n, m; cin >> n >> m;

    if (m > n) {
        cout << 0 << endl;
        return 0;
    }

    for (int i = 1; i <= n; i++) cin >> v[i];
    for (int i = 1; i <= m; i++) {
        int a, b; cin >> a >> b;
        en[i] = a, out[i] = b;
        adj[a].insert(i);
        adj[b].insert(i);
    }

    queue<int> q;

    for (int i = 1; i <= n; i++) {
        if (adj[i].size() == 1) {
            q.push(i);
        }
    }

    while (!q.empty()) {
        // deg 1
        auto cur = q.front(); q.pop();

        if (adj[cur].size() == 1) {
            int idx = *adj[cur].begin();

            int nxtidx = (en[idx] == cur ? out[idx] : en[idx]);
            ll weight = v[cur];

            v[nxtidx] -= v[cur];
            v[cur] -= v[cur];
            
            calc[idx] = weight;

            adj[cur].erase(idx);
            adj[nxtidx].erase(idx);

            if (adj[nxtidx].size() == 1) q.push(nxtidx);
        }
    }

    if (m == n - 1) {
        for (int i = 1; i <= m; i++) {
            cout << calc[i] * 2 << "\n";
        }
        return 0;
    }

    vector<int> left;

    for (int i = 1; i <= n; i++) {
        if (adj[i].size() == 2) left.push_back(i);
    }

    if (left.size() % 2 == 0) {
        cout << 0 << endl;
        return 0;
    }

    if (left.empty()) {
        // wtf
        cout << 0 << endl;
        return 0;
    }

    int start = left.front();

    dfs(left.front(), -1, left.front());

//    assert(ord.size() == left.size());

//    for (auto x : ord) cout << x << " ";

    ll prev = 0;

    for (int i = 0; i < ord.size() - 1; i++) {
        // assum back ->0 is X

        prev = v[ord[i].first] - prev;

    }

    ll x = (v[ord[0].first] - prev) / 2;

//    cout << x << endl;

    calc[ord[0].second] = x;

    for (int i = 1; i < ord.size(); i++) {
        calc[ord[i].second] = v[ord[i].first] - calc[ord[i-1].second];
    }


    for (int i = 1; i <= m; i++) {
        cout << calc[i] * 2 << "\n";
    }
}

Compilation message

pipes.cpp: In function 'int main()':
pipes.cpp:144:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  144 |     for (int i = 0; i < ord.size() - 1; i++) {
      |                     ~~^~~~~~~~~~~~~~~~
pipes.cpp:157:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  157 |     for (int i = 1; i < ord.size(); i++) {
      |                     ~~^~~~~~~~~~~~
pipes.cpp:134:9: warning: unused variable 'start' [-Wunused-variable]
  134 |     int start = left.front();
      |         ^~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 4 ms 4948 KB Output is correct
3 Correct 3 ms 5076 KB Output is correct
4 Correct 121 ms 17284 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 4 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5076 KB Output is correct
10 Correct 3 ms 5076 KB Output is correct
11 Correct 3 ms 5076 KB Output is correct
12 Correct 3 ms 5076 KB Output is correct
13 Correct 81 ms 14760 KB Output is correct
14 Correct 120 ms 16668 KB Output is correct
15 Correct 95 ms 17348 KB Output is correct
16 Correct 74 ms 15436 KB Output is correct
17 Correct 99 ms 17312 KB Output is correct
18 Correct 107 ms 17348 KB Output is correct
19 Correct 73 ms 17204 KB Output is correct
20 Correct 2 ms 4948 KB Output is correct
21 Correct 3 ms 5076 KB Output is correct
22 Correct 98 ms 17356 KB Output is correct
23 Correct 76 ms 14728 KB Output is correct
24 Correct 111 ms 17352 KB Output is correct
25 Correct 80 ms 15232 KB Output is correct

Subtask #2
44.0740740741 / 70.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 4948 KB Output isn't correct
2 Incorrect 4 ms 5076 KB Output isn't correct
3 Correct 77 ms 16456 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Incorrect 3 ms 4948 KB Output isn't correct
8 Incorrect 3 ms 4948 KB Output isn't correct
9 Correct 3 ms 4948 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 4 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Incorrect 3 ms 4948 KB Output isn't correct
15 Incorrect 3 ms 5076 KB Output isn't correct
16 Incorrect 3 ms 5076 KB Output isn't correct
17 Correct 3 ms 5076 KB Output is correct
18 Correct 2 ms 4948 KB Output is correct
19 Correct 3 ms 4948 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Incorrect 3 ms 5076 KB Output isn't correct
23 Incorrect 66 ms 15684 KB Output isn't correct
24 Incorrect 95 ms 18020 KB Output isn't correct
25 Correct 72 ms 16428 KB Output is correct
26 Correct 3 ms 4908 KB Output is correct
27 Correct 2 ms 4948 KB Output is correct
28 Correct 3 ms 4948 KB Output is correct
29 Correct 3 ms 4948 KB Output is correct
30 Incorrect 84 ms 17560 KB Output isn't correct
31 Incorrect 80 ms 18380 KB Output isn't correct
32 Incorrect 99 ms 17504 KB Output isn't correct
33 Correct 89 ms 17148 KB Output is correct
34 Correct 3 ms 5028 KB Output is correct
35 Correct 3 ms 4952 KB Output is correct
36 Correct 3 ms 4948 KB Output is correct
37 Correct 3 ms 4948 KB Output is correct
38 Incorrect 84 ms 17968 KB Output isn't correct
39 Incorrect 97 ms 17380 KB Output isn't correct
40 Incorrect 104 ms 17988 KB Output isn't correct
41 Correct 61 ms 17404 KB Output is correct
42 Correct 2 ms 4948 KB Output is correct
43 Correct 2 ms 4948 KB Output is correct
44 Correct 3 ms 4948 KB Output is correct
45 Correct 2 ms 4948 KB Output is correct
46 Incorrect 85 ms 17804 KB Output isn't correct
47 Incorrect 88 ms 18048 KB Output isn't correct
48 Incorrect 82 ms 18364 KB Output isn't correct
49 Correct 118 ms 16184 KB Output is correct
50 Correct 2 ms 4948 KB Output is correct
51 Correct 2 ms 4948 KB Output is correct
52 Correct 3 ms 4996 KB Output is correct
53 Correct 2 ms 4948 KB Output is correct
54 Incorrect 83 ms 17604 KB Output isn't correct