Submission #1113841

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113841		Aviansh	Firefighting (NOI20_firefighting)	C++17	0 / 100	162 ms	25164 KiB

Firefighting

#include <bits/stdc++.h>

using namespace std;

bool dfs(int st, vector<array<int,2>>(&g)[],int dis, int mas, int k, int p){
    bool work = 1;
    if((1<<st)&mas)
        dis=0;
    for(array<int,2>node : g[st]){
        if(node[0]==p)
            continue;
        work&=dfs(node[0],g,dis+node[1],mas,k,st);
    }
    if(dis>=k){
        return 0;
    }
    return work;
}

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n,k;
    cin >> n >> k;
    vector<array<int,2>>g[n];
    bool cas1 = true;
    for(int i = 0;i<n-1;i++){
        int a,b,d;
        cin >> a >> b >> d;
        a--;b--;
        g[a].push_back({b,d});
        g[b].push_back({a,d});
        if(d>=k){
            cas1=0;
        }
    }
    if(cas1){
        cout << n << "\n";
        for(int i = 1;i<=n;i++){
            cout << i << " ";
        }
        return 0;
    }
    cout << dfs(1,g,0,54,k,-1);
    return 0;
    if(n<=17){
        int mx=(1<<n)-1;
        for(int mask = 1;mask<(1<<n);mask++){
            for(int i = 0;i<n;i++){
                if(mask&(1<<i)){
                    if(dfs(i,g,0,mask,k,-1)){
                        if(__builtin_popcount(mask)<=__builtin_popcount(mx)){
                            mx=mask;
                        }
                    }
                    break;
                }
            }
        }
        cout << __builtin_popcount(mx) << "\n";
        for(int i = 0;i<n;i++){
            if((1<<i)&mx){
                cout << i+1 << " ";
            }
        }
    }
    return 0;
}

• Subtask 1: 0 / 3
• Subtask 2: 0 / 5
• Subtask 3: 0 / 9
• Subtask 4: 0 / 19
• Subtask 5: 0 / 26
• Subtask 6: 0 / 38