Submission #1097649

# Submission time Handle Problem Language Result Execution time Memory
1097649 2024-10-07T20:04:31 Z SiddharthJoshi6263 Race (IOI11_race) C++17
9 / 100
287 ms 60392 KB
#include <bits/stdc++.h>

using namespace std;

// #ifdef ONLINE_JUDGE
// #define debug(...)
// #else
// #include "debug.h"
// #endif

#define f first
#define s second
#define pb push_back
#define all(x) x.begin(), x.end()
#define sz(x) (long long)(x).size()
#define pii pair<long long, long long>

long long ANS = INT_MAX;

void dfs_sze(long long u, long long par, vector<vector<pii>> &adj, vector<long long> &sze, vector<long long> &len, vector<long long> &depth) {
    sze[u] = 1;
    for (auto v : adj[u]) {
        if (v.f != par) {
            len[v.f] = len[u] + v.s;
            depth[v.f] = depth[u] + 1;
            dfs_sze(v.f, u, adj, sze, len, depth);
            sze[u] += sze[v.f];
        }
    }
}

void small_to_large_merging(long long K, long long u, long long par, vector<long long> &sze, vector<long long> &len, vector<long long> &depth, vector<vector<pii>> &adj, vector<multiset<pii>> &sets) {
    long long big = -1, big_wt = 0;
    for (auto v : adj[u]) {
        if (v.f != par) {
            if (big == -1 || sze[big] < sze[v.f]) {
                big = v.f;
                big_wt = v.s;
            }
        }
    }
    if (big == -1) {
        return;
    }
    small_to_large_merging(K, big, u, sze, len, depth, adj, sets);
    vector<pii> smalls1, smalls2;
    for (auto x : adj[u]) {
        if (x.f != par && x.f != big) {
            small_to_large_merging(K, x.f, u, sze, len, depth, adj, sets);
            long long edge_wt = x.s;
            for (auto y : sets[x.f]) {
                smalls1.pb({y.f, y.s});
                long long act_len = y.f - len[x.f] + edge_wt + big_wt;
                long long act_dep = y.s - depth[x.f] + 2;
                long long find_len = K - act_len;
                if (find_len <= 0)continue;
                long long search = find_len + len[big];
                pii finds = {search, -1ll};
                auto vals = sets[big].lower_bound(finds);
                if (vals != sets[big].end()) {
                    if (vals->f == search) {
                        ANS = min(ANS, act_dep + vals->s - depth[big]);
                    }
                }
            }
            for (auto y : sets[x.f]) {
                smalls2.pb({y.f + edge_wt - big_wt, y.s});
                sets[big].insert({y.f + edge_wt - big_wt, y.s});
            }
        }
    }
    for (auto x : smalls1) {
        sets[big].insert(x);
    }
    for (auto x : smalls2) {
        sets[big].erase(sets[big].find(x));
    }
    sets[u].swap(sets[big]);
    sets[u].insert({len[u], depth[u]});
    pii finds = {K + len[u], -1ll};
    auto vals = sets[u].lower_bound(finds);
    if (vals != sets[u].end()) {
        if (vals->f == K + len[u]) {
            ANS = min(ANS, vals->s - depth[u]);
        }
    }
}

int best_path (int N, int k, int H[][2], int L[]) {
    long long n = N, K = k;
    vector<vector<pii>> adj(n);
    for (long long i = 0; i < n - 1; i++) {
        adj[H[i][0]].pb({H[i][1], L[i]});
        adj[H[i][1]].pb({H[i][0], L[i]});
    }
    vector<long long> sze(n, 0);
    vector<long long> len(n, 0);
    vector<long long> depth(n, 0);
    dfs_sze(0, -1, adj, sze, len, depth);
    vector<multiset<pii>> sets(n);
    for (long long i = 0; i < n; i++) {
        sets[i].insert({len[i], depth[i]});
    }
    small_to_large_merging(K, 0, -1, sze, len, depth, adj, sets);
    if (ANS == INT_MAX) {
        return -1;
    }
    return ANS;
}

// void solve() {
//     int n, K;
//     cin >> n >> K;
//     int H[n - 1][2];
//     int L[n - 1];
//     for (long long i = 0; i < n - 1; i++) {
//         cin >> H[i][0] >> H[i][1];
//     }
//     for (long long i = 0; i < n - 1; i++) {
//         cin >> L[i];
//     }
//     cout << best_path(n, K, H, L) << endl;
// }

// signed main() {
//     ios_base::sync_with_stdio(false);
//     cin.tie(NULL);
//     cout.tie(NULL);
//     long long zz = 1;
//     // cin >> zz;
//     for (long long i = 1; i <= zz; i++) {
//         // cout << "Case #" << i << ": ";
//         solve();
//     }
//     return 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 0 ms 348 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 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 452 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
# 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 0 ms 348 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 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 452 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 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 348 KB Output is correct
21 Correct 2 ms 860 KB Output is correct
22 Correct 2 ms 860 KB Output is correct
23 Incorrect 1 ms 860 KB Output isn't correct
24 Halted 0 ms 0 KB -
# 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 0 ms 348 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 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 452 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 286 ms 60392 KB Output is correct
20 Correct 278 ms 57524 KB Output is correct
21 Incorrect 287 ms 59964 KB Output isn't correct
22 Halted 0 ms 0 KB -
# 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 0 ms 348 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 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 452 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 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 348 KB Output is correct
21 Correct 2 ms 860 KB Output is correct
22 Correct 2 ms 860 KB Output is correct
23 Incorrect 1 ms 860 KB Output isn't correct
24 Halted 0 ms 0 KB -