Submission #767912

#	Time	Username	Problem	Language	Result	Execution time	Memory
767912		raysh07	Paths (BOI18_paths)	C++17	100 / 100	414 ms	100488 KiB

paths

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define INF (int)1e18
#define f first
#define s second

mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
int n, m, k;
const int N = 3e5 + 69;
const int K = 5;
int dp[N][1 << K];
vector <int> adj[N];
int a[N];

int cnt(int x){
    if (x == 0) return 0;
    return cnt(x/2) + x % 2;
}

void Solve() 
{
    cin >> n >> m >> k;
    
    for (int i = 1; i <= n; i++) {
        cin >> a[i], a[i]--;
        dp[i][1 << a[i]] = 1;
    }
    
    for (int i = 1; i <= m; i++){
        int u, v; cin >> u >> v;
        
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    
    for (int it = 2; it <= 5; it++){
        vector <int> ok;
        for (int mask = 1; mask < 32; mask++){
            if (cnt(mask) == it) ok.push_back(mask);
        }
        for (int i = 1; i <= n; i++){
            for (int j : adj[i]){
                for (auto mask : ok){
                    if (mask >> a[i] & 1){
                        dp[i][mask] += dp[j][mask ^ (1 << a[i])];
                    }
                }
            }
        }
    }
    
    int ans = 0;
    for (int i = 1; i <= n; i++){
        for (int j = 1; j < 32; j++){
            ans += dp[i][j];
        }
    }
    
    cout << ans - n << "\n";
}

int32_t main() 
{
    auto begin = std::chrono::high_resolution_clock::now();
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
//    cin >> t;
    for(int i = 1; i <= t; i++) 
    {
        //cout << "Case #" << i << ": ";
        Solve();
    }
    auto end = std::chrono::high_resolution_clock::now();
    auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
    cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n"; 
    return 0;
}

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30