oj.uz

Submission #525224

# Submission time Handle Problem Language Result Execution time Memory
525224 2022-02-11T06:52:40 Z mjhmjh1104 Firefighting (NOI20_firefighting) C++17
100 / 100
 340 ms 42044 KB 
#include <cstdio>
#include <vector>
#include <utility>
#include <algorithm>
using namespace std;

int n;
long long k;
vector<pair<int, int>> adj[300006];
vector<int> res;

pair<long long, bool> dfs(int x, int prev = -1) {
    long long rev = 0;
    bool fine = false;
    vector<long long> v;
    for (auto &i: adj[x]) if (i.first != prev) {
        pair<long long, bool> p = dfs(i.first, x);
        long long t = p.first + i.second;
        if (!p.second && t > k) {
            res.push_back(i.first);
            t = i.second - k;
            p.second = true;
        }
        if (t < 0) rev = max(rev, -t), fine = true;
        else if (!p.second) v.push_back(t);
        else if (!t) fine = true;
    }
    sort(v.rbegin(), v.rend());
    if (v.empty()) return { -rev, fine };
    if (v[0] <= rev) return { -rev, true };
    if (v[0] >= k) {
        res.push_back(x);
        return { -k, true };
    }
    return { v[0], false };
}

int main() {
    scanf("%d%lld", &n, &k);
    for (int i = 0; i < n - 1; i++) {
        int a, b, c;
        scanf("%d%d%d", &a, &b, &c);
        a--, b--;
        adj[a].push_back({ b, c });
        adj[b].push_back({ a, c });
    }
    if (n == 1) {
        puts("1\n1");
        return 0;
    }
    if (n == 2) {
        if (adj[0][0].second <= k) puts("1\n1");
        else puts("2\n1 2");
        return 0;
    }
    if (!dfs(0).second) res.push_back(0);
    printf("%d\n", (int)res.size());
    for (auto &i: res) printf("%d ", i + 1);
}

Compilation message

Firefighting.cpp: In function 'int main()':
Firefighting.cpp:39:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |     scanf("%d%lld", &n, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~
Firefighting.cpp:42:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |         scanf("%d%d%d", &a, &b, &c);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 262 ms 21680 KB Output is correct
2 Correct 265 ms 21724 KB Output is correct
3 Correct 74 ms 12680 KB Output is correct
4 Correct 255 ms 21268 KB Output is correct
5 Correct 4 ms 7244 KB Output is correct
6 Correct 3 ms 7244 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 7244 KB Output is correct
2 Correct 3 ms 7244 KB Output is correct
3 Correct 3 ms 7244 KB Output is correct
4 Correct 3 ms 7244 KB Output is correct
5 Correct 4 ms 7244 KB Output is correct
6 Correct 4 ms 7320 KB Output is correct
7 Correct 4 ms 7372 KB Output is correct
8 Correct 4 ms 7372 KB Output is correct
9 Correct 5 ms 7324 KB Output is correct
10 Correct 4 ms 7244 KB Output is correct
11 Correct 4 ms 7244 KB Output is correct
12 Correct 4 ms 7244 KB Output is correct
13 Correct 4 ms 7244 KB Output is correct
14 Correct 3 ms 7324 KB Output is correct
15 Correct 3 ms 7244 KB Output is correct

Subtask #3
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 7244 KB Output is correct
2 Correct 3 ms 7244 KB Output is correct
3 Correct 5 ms 7244 KB Output is correct
4 Correct 3 ms 7244 KB Output is correct
5 Correct 4 ms 7244 KB Output is correct
6 Correct 4 ms 7244 KB Output is correct
7 Correct 4 ms 7320 KB Output is correct
8 Correct 3 ms 7244 KB Output is correct
9 Correct 4 ms 7324 KB Output is correct
10 Correct 4 ms 7244 KB Output is correct
11 Correct 4 ms 7244 KB Output is correct
12 Correct 4 ms 7244 KB Output is correct
13 Correct 4 ms 7244 KB Output is correct
14 Correct 4 ms 7288 KB Output is correct
15 Correct 3 ms 7244 KB Output is correct
16 Correct 4 ms 7244 KB Output is correct
17 Correct 4 ms 7244 KB Output is correct
18 Correct 4 ms 7244 KB Output is correct
19 Correct 4 ms 7244 KB Output is correct
20 Correct 3 ms 7244 KB Output is correct
21 Correct 4 ms 7244 KB Output is correct
22 Correct 4 ms 7236 KB Output is correct
23 Correct 3 ms 7244 KB Output is correct
24 Correct 3 ms 7316 KB Output is correct
25 Correct 4 ms 7244 KB Output is correct
26 Correct 4 ms 7244 KB Output is correct

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 277 ms 21628 KB Output is correct
2 Correct 115 ms 14408 KB Output is correct
3 Correct 125 ms 17396 KB Output is correct
4 Correct 103 ms 16036 KB Output is correct
5 Correct 4 ms 7320 KB Output is correct
6 Correct 4 ms 7244 KB Output is correct
7 Correct 254 ms 23628 KB Output is correct
8 Correct 243 ms 23644 KB Output is correct
9 Correct 244 ms 23656 KB Output is correct
10 Correct 263 ms 23656 KB Output is correct
11 Correct 277 ms 24876 KB Output is correct
12 Correct 182 ms 19552 KB Output is correct
13 Correct 116 ms 14824 KB Output is correct
14 Correct 176 ms 18752 KB Output is correct
15 Correct 216 ms 20900 KB Output is correct
16 Correct 235 ms 21568 KB Output is correct
17 Correct 183 ms 19816 KB Output is correct
18 Correct 201 ms 19460 KB Output is correct

Subtask #5
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 7372 KB Output is correct
2 Correct 6 ms 7372 KB Output is correct
3 Correct 9 ms 7372 KB Output is correct
4 Correct 4 ms 7372 KB Output is correct
5 Correct 5 ms 7592 KB Output is correct
6 Correct 9 ms 7596 KB Output is correct
7 Correct 5 ms 7628 KB Output is correct
8 Correct 5 ms 7580 KB Output is correct
9 Correct 5 ms 7500 KB Output is correct
10 Correct 5 ms 7500 KB Output is correct
11 Correct 5 ms 7628 KB Output is correct
12 Correct 5 ms 7372 KB Output is correct
13 Correct 6 ms 7532 KB Output is correct
14 Correct 6 ms 7500 KB Output is correct
15 Correct 5 ms 7416 KB Output is correct
16 Correct 5 ms 7372 KB Output is correct
17 Correct 5 ms 7372 KB Output is correct
18 Correct 6 ms 7500 KB Output is correct
19 Correct 8 ms 7336 KB Output is correct
20 Correct 5 ms 7372 KB Output is correct
21 Correct 8 ms 7500 KB Output is correct

Subtask #6
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 254 ms 18128 KB Output is correct
2 Correct 270 ms 18012 KB Output is correct
3 Correct 300 ms 18712 KB Output is correct
4 Correct 91 ms 12660 KB Output is correct
5 Correct 308 ms 35448 KB Output is correct
6 Correct 321 ms 33112 KB Output is correct
7 Correct 340 ms 40560 KB Output is correct
8 Correct 334 ms 38908 KB Output is correct
9 Correct 286 ms 30852 KB Output is correct
10 Correct 288 ms 29376 KB Output is correct
11 Correct 327 ms 42044 KB Output is correct
12 Correct 199 ms 15252 KB Output is correct
13 Correct 321 ms 31860 KB Output is correct
14 Correct 307 ms 26848 KB Output is correct
15 Correct 288 ms 19012 KB Output is correct
16 Correct 249 ms 18292 KB Output is correct
17 Correct 242 ms 18116 KB Output is correct
18 Correct 254 ms 18832 KB Output is correct
19 Correct 171 ms 15556 KB Output is correct
20 Correct 93 ms 11944 KB Output is correct
21 Correct 250 ms 18924 KB Output is correct