Submission #960869

# Submission time Handle Problem Language Result Execution time Memory
960869 2024-04-11T06:56:51 Z Ghetto Chase (CEOI17_chase) C++17
40 / 100
348 ms 524288 KB
#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
using lint = long long;
const int MAX_N = 1e5 + 5, MAX_K = 1e2 + 5;

int n, k;
lint val[MAX_N];
vector<int> adj[MAX_N], adj_ind[MAX_N]; // adj_ind[u][i] = ind of adj list u is for adj[u][i]
void init() {
    for (int i = 1; i <= n; i++) {
        adj[i].push_back(0);
        adj_ind[i].push_back(0);
    }
}

vector<int> seen[MAX_N];
vector<pii> topo_order;
void dfs(int u, int prev) {
    seen[u][prev] = 1;
    for (int i = 1; i < adj[u].size(); i++) {
        if (i == prev) continue;
        int v = adj[u][i];
        if (seen[v][adj_ind[u][i]] == 1) assert(true == false);
        if (!seen[v][adj_ind[u][i]]) dfs(v, adj_ind[u][i]);
    }
    seen[u][prev] = 2;
    topo_order.push_back({u, prev});
}

vector<lint> dp[MAX_N][MAX_K];
void precomp() {
    for (int i = 1; i <= n; i++)
        seen[i].resize(adj[i].size() + 2);
    
    for (int i = 1; i <= n; i++)
        dfs(i, 0);
    reverse(topo_order.begin(), topo_order.end());
    assert(topo_order.size() <= 3 * 1e5);

    for (int i = 1; i <= n; i++) {
        for (int c = 0; c <= k; c++) {
            dp[i][c].resize(adj[i].size() + 2);
        }
    }
}

int main() {
    // freopen("chase.in", "r", stdin);

    cin >> n >> k;
    init();

    for (int i = 1; i <= n; i++) cin >> val[i];
    for (int i = 1; i < n; i++) {
        int u, v; cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);

        int u_ind = adj[u].size() - 1, v_ind = adj[v].size() - 1;
        adj_ind[u].push_back(v_ind);
        adj_ind[v].push_back(u_ind);
    }

    precomp();

    for (int c = 1; c <= k; c++) {
        for (int j = topo_order.size() - 1; j >= 0; j--) {
            int u = topo_order[j].first, prev = topo_order[j].second;

            lint leave = 0;
            for (int i = 1; i < adj[u].size(); i++)
                if (i != prev) leave = max(leave, dp[adj[u][i]][c][adj_ind[u][i]]);

            lint take = 0;
            for (int i = 1; i < adj[u].size(); i++)
                if (i != prev) take = max(take, dp[adj[u][i]][c - 1][adj_ind[u][i]]);
            for (int i = 1; i < adj[u].size(); i++)
                if (i != prev) take += val[adj[u][i]];
            
            dp[u][c][prev] = max(take, leave);
        }
    }

    lint ans = 0;
    for (int i = 1; i <= n; i++) ans = max(ans, dp[i][k][0]);
    cout << ans << '\n';
}

Compilation message

chase.cpp: In function 'void dfs(int, int)':
chase.cpp:21:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for (int i = 1; i < adj[u].size(); i++) {
      |                     ~~^~~~~~~~~~~~~~~
chase.cpp: In function 'int main()':
chase.cpp:72:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |             for (int i = 1; i < adj[u].size(); i++)
      |                             ~~^~~~~~~~~~~~~~~
chase.cpp:76:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |             for (int i = 1; i < adj[u].size(); i++)
      |                             ~~^~~~~~~~~~~~~~~
chase.cpp:78:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |             for (int i = 1; i < adj[u].size(); i++)
      |                             ~~^~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 58 ms 254036 KB Output is correct
2 Correct 56 ms 254036 KB Output is correct
3 Correct 59 ms 254036 KB Output is correct
4 Correct 61 ms 254012 KB Output is correct
5 Correct 62 ms 254020 KB Output is correct
6 Correct 60 ms 254056 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 58 ms 254036 KB Output is correct
2 Correct 56 ms 254036 KB Output is correct
3 Correct 59 ms 254036 KB Output is correct
4 Correct 61 ms 254012 KB Output is correct
5 Correct 62 ms 254020 KB Output is correct
6 Correct 60 ms 254056 KB Output is correct
7 Correct 73 ms 259412 KB Output is correct
8 Correct 60 ms 254548 KB Output is correct
9 Correct 82 ms 254520 KB Output is correct
10 Correct 80 ms 259472 KB Output is correct
11 Correct 63 ms 255568 KB Output is correct
12 Correct 61 ms 254484 KB Output is correct
# Verdict Execution time Memory Grader output
1 Runtime error 348 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 58 ms 254036 KB Output is correct
2 Correct 56 ms 254036 KB Output is correct
3 Correct 59 ms 254036 KB Output is correct
4 Correct 61 ms 254012 KB Output is correct
5 Correct 62 ms 254020 KB Output is correct
6 Correct 60 ms 254056 KB Output is correct
7 Correct 73 ms 259412 KB Output is correct
8 Correct 60 ms 254548 KB Output is correct
9 Correct 82 ms 254520 KB Output is correct
10 Correct 80 ms 259472 KB Output is correct
11 Correct 63 ms 255568 KB Output is correct
12 Correct 61 ms 254484 KB Output is correct
13 Runtime error 348 ms 524288 KB Execution killed with signal 9
14 Halted 0 ms 0 KB -