Submission #1106143

#	Time	Username	Problem	Language	Result	Execution time	Memory
1106143		votranngocvy	Cities (BOI16_cities)	C++14	100 / 100	1411 ms	51456 KiB

cities

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e5 + 5;
const int inf = 0x3f3f3f3f3f3f3f3f;
const int M = (1 << 5) + 5;
int a[10],dp[M][N];
vector<pii>g[N];

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int n,k,m;
    cin >> n >> k >> m;
    for (int i = 0; i < k; i++) cin >> a[i];
    for (int i = 1; i <= m; i++) {
        int u,v,w;
        cin >> u >> v >> w;
        g[u].push_back({v,w});
        g[v].push_back({u,w});
    }
    for (int mask = 0; mask < (1 << k); mask++)
        for (int i = 1; i <= n; i++) dp[mask][i] = inf;
    for (int i = 0; i < k; i++) dp[(1 << i)][a[i]] = 0;
    for (int mask = 1; mask < (1 << k); mask++) {
        for (int sub = mask & (mask - 1); sub > 0; sub = mask & (sub - 1)) 
            for (int i = 1; i <= n; i++)
                dp[mask][i] = min(dp[mask][i],dp[sub][i] + dp[mask ^ sub][i]);
        priority_queue<pii,vector<pii>,greater<pii>>q;
        for (int i = 1; i <= n; i++)
            if (dp[mask][i] < inf) q.push({dp[mask][i],i});
        while (!q.empty()) {
            int u = q.top().se,c = q.top().fi;
            q.pop();
            if (dp[mask][u] != c) continue;
            for (auto x: g[u]) {
                int v = x.fi,w = x.se;
                if (dp[mask][v] > dp[mask][u] + w) {
                    dp[mask][v] = dp[mask][u] + w;
                    q.push({dp[mask][v],v});
                }
            }
        }
    }
    int ans = inf;
    for (int i = 1; i <= n; i++) ans = min(ans,dp[(1 << k) - 1][i]);
    cout << ans << "\n";
}

• Subtask 1: 22 / 22
• Subtask 2: 14 / 14
• Subtask 3: 15 / 15
• Subtask 4: 23 / 23
• Subtask 5: 26 / 26