Submission #1331659

#	Time	Username	Problem	Language	Result	Execution time	Memory
1331659		Naa	Cities (BOI16_cities)	C++20	100 / 100	2060 ms	49384 KiB

cities

#include <bits/stdc++.h>
using namespace std;
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());

using i32 = long long;

#define all(a) (a).begin(), (a).end()
#define open(x) if(fopen(#x ".inp", "r")) {freopen(#x ".inp", "r", stdin); freopen(#x ".out", "w", stdout);}

template<class X, class Y> bool mimi(X &x, const Y &y) {if(x > y) {x = y; return 1;} return 0;}
template<class X, class Y> bool mama(X &x, const Y &y) {if(x < y) {x = y; return 1;} return 0;}

const i32 N = 1e5 + 5;
const i32 M = 1000000007;
const i32 inf = 1000000009;
const i32 infll = (i32)1000000000000000018;

struct edge {i32 u, v, c;};
struct Edge {i32 v, c;};
i32 n, k, m;
i32 dp[N][1 << 5], spec[N];
vector<i32> sm[N];
vector<Edge> g[N];
vector<edge> ee;

void sad(i32 testID) {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> n >> k >> m;

    for(i32 i = 0; i < k; i ++) {
        cin >> spec[i];
        spec[i] --;
    }

    for(i32 i = 0; i < m; i ++) {
        i32 u, v; i32 c;
        cin >> u >> v >> c;
        u --; v --;
        ee.push_back({u, v, c});
        g[u].push_back({v, c});
        g[v].push_back({u, c});
    }

    memset(dp, 0x3f, sizeof dp);
    for(i32 i = 0; i < k; i ++)
        dp[spec[i]][1 << i] = 0;

    for(i32 mask = 1; mask < (1 << k); mask ++) {
        for(i32 sub = (mask - 1) & mask; sub; sub = (sub - 1) & mask) {
            for(i32 u = 0; u < n; u ++) {
                mimi(dp[u][mask], dp[u][sub] + dp[u][mask ^ sub]);
            }
        }
        priority_queue<pair<i32,i32>, vector<pair<i32,i32>>, greater<>> pq;
        vector<bool> vis(n, false);

        for(i32 i = 0; i < n; i ++) 
            if(dp[i][mask] < infll) pq.push({dp[i][mask], i});
        while(!pq.empty()) {
            pair<i32, i32> temp = pq.top(); pq.pop();
            i32 d = temp.first, u = temp.second;
            if(vis[u]) continue;
            vis[u] = true;

            for(auto &e : g[u]) {
                if(mimi(dp[e.v][mask], d + e.c)) 
                    pq.push({dp[e.v][mask], e.v});
            }
        }
    }

    i32 res = infll;
    for(i32 i = 0; i < n; i ++) mimi(res, dp[i][(1 << k) - 1]);
    cout << res << "\n";
}

signed main() {
    auto begin = std::chrono::high_resolution_clock::now();
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

    open(task)

    i32 t = 1;
    // cin >> t;
    for(i32 testID = 1; testID <= t; testID ++) {
        // cout << "Case #" << testID << ":\n";
        sad(testID);
    }
    auto end = std::chrono::high_resolution_clock::now();
    auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
    // cerr << endl << "Time measured: " << elapsed.count() * 1e-9 << " seconds." << endl; 
    return 0;
}

Compilation message (stderr)

cities.cpp: In function 'int main()':
cities.cpp:8:51: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 | #define open(x) if(fopen(#x ".inp", "r")) {freopen(#x ".inp", "r", stdin); freopen(#x ".out", "w", stdout);}
      |                                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
cities.cpp:84:5: note: in expansion of macro 'open'
   84 |     open(task)
      |     ^~~~
cities.cpp:8:83: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 | #define open(x) if(fopen(#x ".inp", "r")) {freopen(#x ".inp", "r", stdin); freopen(#x ".out", "w", stdout);}
      |                                                                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
cities.cpp:84:5: note: in expansion of macro 'open'
   84 |     open(task)
      |     ^~~~

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