Submission #96937

#	Time	Username	Problem	Language	Result	Execution time	Memory
96937		Kastanda	Cities (BOI16_cities)	C++11	100 / 100	4274 ms	42572 KiB

cities

#include<bits/stdc++.h>
using namespace std;
const int N = 100005, K = 5;
int n, m, k, A[K];
long long dp[1 << K][N];
vector < pair < int , int > > Adj[N];
int main()
{
    scanf("%d%d%d", &n, &k, &m);
    memset(dp, 63, sizeof(dp));
    for (int i = 0; i < k; i++)
        scanf("%d", &A[i]), dp[1 << i][A[i]] = 0;
    for (int i = 1; i <= m; i++)
    {
        int v, u, w;
        scanf("%d%d%d", &v, &u, &w);
        Adj[v].push_back({u, w});
        Adj[u].push_back({v, w});
    }
    priority_queue < pair < long long , int > > Pq;
    for (int mask = 1; mask < (1 << k); mask ++)
    {
        if (__builtin_popcount(mask) > 1)
            for (int v = 1; v <= n; v ++)
                for (int sub = mask; sub; sub = (sub - 1) & mask)
                    if (sub && (sub ^ mask))
                        for (auto &u : Adj[v])
                            if (dp[mask][v] > dp[sub][v] + dp[mask ^ sub][u.first] + u.second)
                                dp[mask][v] = dp[sub][v] + dp[mask ^ sub][u.first] + u.second;
        for (int v = 1; v <= n; v ++)
            Pq.push({-dp[mask][v], v});
        while (Pq.size())
        {
            int v = Pq.top().second;
            long long d = -Pq.top().first;
            Pq.pop();
            if (d > dp[mask][v])
                continue;
            for (auto &u : Adj[v])
                if (dp[mask][u.first] > dp[mask][v] + u.second)
                    dp[mask][u.first] = dp[mask][v] + u.second, Pq.push({-dp[mask][u.first], u.first});
        }
    }
    return !printf("%lld\n", dp[(1 << k) - 1][A[0]]);
}

Compilation message (stderr)

cities.cpp: In function 'int main()':
cities.cpp:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d", &n, &k, &m);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
cities.cpp:12:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &A[i]), dp[1 << i][A[i]] = 0;
         ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
cities.cpp:16:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d", &v, &u, &w);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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