Submission #955718

#	Time	Username	Problem	Language	Result	Execution time	Memory
955718		TimAni	Burza (COCI16_burza)	C++17	160 / 160	38 ms	860 KiB

burza

//start-time: 2024-03-31 11:42:07
#include <bits/stdc++.h>

using namespace std;
using ll = long long;

void solve(){
    int N, K;
    cin >> N >> K;
    vector<vector<int>> tree(N);
    for(int i = 0; i < N - 1; i++){
        int u, v;
        cin >> u >> v;
        u--; v--;
        tree[u].push_back(v);
        tree[v].push_back(u);
    }
    
    if(K * K >= N){
        cout << "DA\n";
        return;
    }
    
    vector<vector<int>> depths(K + 1);
    vector<array<int, 2>> intervals(N, {N + 1, 0});
    int cnt = 0;
    auto dfs = [&](int u, int p, int d, auto&& dfs) -> bool {
        bool deepEnought = d == K;
        if(deepEnought){
            cnt++;
            intervals[u][0] = cnt;
            intervals[u][1] = cnt;
        }
        for(auto v : tree[u]){
            if(v != p && d < K){
                deepEnought |= dfs(v, u, d + 1, dfs);
                if(deepEnought){
                    intervals[u][0] = min(intervals[v][0], intervals[u][0]);
                    intervals[u][1] = max(intervals[v][1], intervals[u][1]);
                }
            }
        }
        if(deepEnought)
            depths[d].push_back(u);
        return deepEnought;
    };
    
    dfs(0, -1, 0, dfs);
    
    // max # covered with depths specified from mask
    vector<int> dp(1 << K, 0);
    dp[0] = 0;
    for(int mask = 1; mask < (1 << K); mask++){
        for(int depth = 0; depth < K; depth++){
            if(mask & (1<<depth)){
                int prev = dp[mask ^ (1<<depth)];
                for(auto v : depths[depth + 1]){
                    auto [l, r] = intervals[v];
                    if(l <= prev + 1){
                        dp[mask] = max(dp[mask], r);
                    }
                }
            }
        }
        if(dp[mask] == cnt){
            cout << "DA\n";
            return;
        }
    }
    cout << "NE\n";
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    int T = 1;
    //cin >> T;
    while(T--) solve();
    return 0;
}

• Subtask 1: 16 / 16
• Subtask 2: 16 / 16
• Subtask 3: 16 / 16
• Subtask 4: 16 / 16
• Subtask 5: 16 / 16
• Subtask 6: 16 / 16
• Subtask 7: 16 / 16
• Subtask 8: 16 / 16
• Subtask 9: 16 / 16
• Subtask 10: 16 / 16