Submission #821277

#	Time	Username	Problem	Language	Result	Execution time	Memory
821277		Jan636	Burza (COCI16_burza)	C++14	0 / 160	244 ms	948 KiB

burza

//Bitmask DP Solution
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define ms(x, a) memset(x, a, sizeof(x))
const int INF = 0x3f3f3f3f;
//===========================================
const int MAX = 405;
vector<int> adj[MAX];
int dep[MAX], dp[1<<19], l[MAX], r[MAX], curr, n, k;

void dfs(int v, int p){
    if (dep[v] == k){ l[v] = r[v] = ++curr; return; }
    for (int u: adj[v]){
        if (u == p) continue;
        dep[u] = dep[v]+1;
        dfs(u, v);
        l[v] = min(l[v], l[u]);
        r[v] = max(r[v], r[u]);
    }
}

int main(){
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> k;
    ms(l, INF); ms(r, 0);
    if (k >= 20){ cout << "NE\n"; return 0; }
    for (int i = 1; i < n; i++){
        int a, b; cin >> a >> b;
        adj[a].pb(b);
        adj[b].pb(a);
    }
    dfs(1, -1);
    for (int mask = 1; mask < 1<<k; mask++){
        dp[mask] = -INF;
        for (int i = 1; i <= n; i++){
            if (!dep[i] || !(mask&(1<<(dep[i]-1)))) continue;
            if (dp[mask^(1<<(dep[i]-1))]+1 >= l[i]) dp[mask] = max({dp[mask], r[i], dp[mask^(1<<(dep[i]-1))]});
        }
    }
    cout << (dp[(1<<k)-1] == curr? "DA\n" : "NE\n");
}

• Subtask 1: 0 / 16
• Subtask 2: 0 / 16
• Subtask 3: 0 / 16
• Subtask 4: 0 / 16
• Subtask 5: 0 / 16
• Subtask 6: 0 / 16
• Subtask 7: 0 / 16
• Subtask 8: 0 / 16
• Subtask 9: 0 / 16
• Subtask 10: 0 / 16