дейкстра

#include "bits/stdc++.h"
//speed coding handle

#define mp make_pair
#define cve(tpy) for (auto i : tpy) {for(auto j : i){cout << j << " ";  }cout << "\n";} ;
#define f first
#define s second
#define loop(i, x, n) for (int i = x; i < n; i++)
#define joop(x, n) for (ll j = x; j < n; j++)
#define lp(n) for (ll i = 0; i < n; i++)
#define err cout << "ERROR" << endl;
#define all(x) x.begin(), x.end()
#define pb push_back
#define sz(x) x.size()
#define rndm rng()

// types
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
typedef long long ll;
typedef long double ld;

// types of data
#define inf 1000000000
#define infll 1000000000000000000
#define INF ll(1e9)

#define md 998244353
#define mod 1000000009
//#define K 239017

#define DEBUG 1
using namespace std;
mt19937_64 rng(113113);
uniform_int_distribution<ll> drist;
//const int INF = std::numeric_limits<int>::max();
const int MAX_N = 50;

int N; // количество локаций
float graph[MAX_N][MAX_N]; // матрица смежности
float speed[3]; // скорости роботов

void dijkstra(int start, float dist[], float r_speed) {
    bool visited[MAX_N] = {false};
    for (int i = 0; i < N; ++i) {
        dist[i] = INF;
    }
    dist[start] = 0;

    for (int i = 0; i < N; ++i) {
        int u = -1;
        for (int j = 0; j < N; ++j) {
            if (!visited[j] && (u == -1 || dist[j] < dist[u])) {
                u = j;
            }
        }

        if (dist[u] == INF) break;
        visited[u] = true;

        for (int v = 0; v < N; ++v) {
            if (graph[u][v] && dist[u] + graph[u][v] / r_speed < dist[v]) {
                dist[v] = dist[u] + graph[u][v]/r_speed;
            }
        }
    }
}

int main() {
    freopen("text.txt", "r", stdin);
    int m;
    cin >> N >> m;

    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < N; ++j) {
            cin >> graph[i][j];
        }
    }

//    int I1, I2, I3;
//    cin >> I1 >> I2 >> I3;
//    cin >> speed[0] >> speed[1] >> speed[2];
    float mind = inf;
    int I[3];
    loop(i, 0, m){
        cin >> I[i];
    }
    loop(i, 0, m){
        cin >> speed[i];
//        speed[i] /=2;
    }
    float distI1[MAX_N], distI2[MAX_N], distI3[MAX_N];
    float d[3][MAX_N];
//    cout << I[0] << " ";
    loop(i, 0, m){
        dijkstra(I[i], d[i], speed[i]);
    }
//    return 1;
//    err

//    dijkstra(I[0], distI1, (float)speed[0]);
//    dijkstra(I[1], distI2, (float)speed[1]);
//    dijkstra(I[2], distI3, (float)speed[2]);
    loop(p, 0, N) {
        float t[3];
        float middleware = 1;

        loop(i, 0, m){
            float dis = d[i][p];
            t[i] = dis;
            middleware = max(middleware, dis);
        }
        if(t[0] == t[1] or t[0] == t[2] or t[1] == t[2]){
            mind = min(mind, middleware);
        }
        continue;
        float dist1 = d[0][p];
        float dist2 = d[1][p];
        float dist3 = d[2][p];
        if (dist1 == dist2 or dist1 == dist3 or dist2 == dist3) {// если пришли в 1 место в 1 время
            if (dist1 == dist2 and dist2 == dist3) {
                mind = min(mind, dist1); // в 1 месте
            } else {
                mind = min(mind, max(max(dist1, dist2), dist3));
            }
        }
    }
    if(mind == inf){
        cout << "Never meet\n";
        return 1;
    }
    cout << "Min dist for robots:" << mind << endl;

    return 1;
//    loop(i, 1, 3){
//        loop(j, 1, 3){
//            loop(k, 1, 3){
//                float distI1[MAX_N], distI2[MAX_N], distI3[MAX_N];
////                err
//
//                dijkstra(I1, distI1, (float)i);
//                dijkstra(I2, distI2, (float)j);
//                dijkstra(I3, distI3, (float)k);
//
//                loop(p, 0, N){
//                    float dist1 = distI1[p];
//                    float dist2 = distI2[p];
//                    float dist3 = distI3[p];
//                    if(dist1 == dist2 or dist1 == dist3 or dist2 == dist3){// если пришли в 1 место в 1 время
//                        if(dist1 == dist2 and dist2 == dist3){
//                            mind = min(mind, dist1);
//                        }else{
//                            mind = min(mind, max(max(dist1, dist2), dist3));
//                        }
//                    }
//                }
//            }
//        }
//    }
//    cout << "Min dist for all robots:" << mind;

//    if (dist1 == INF && dist2 == INF && dist3 == INF) {
//        std::cout << "Meeting of all robots is not possible." << std::endl;
//    } else {
//        int min_dist = std::min({dist1, dist2, dist3});
//        std::cout << "Minimum distance for all robots to meet: " << min_dist << std::endl;
//        if (min_dist == dist1) {
//            std::cout << "Shortest path is from robot starting at location " << I1 << std::endl;
//        } else if (min_dist == dist2) {
//            std::cout << "Shortest path is from robot starting at location " << I2 << std::endl;
//        } else {
//            std::cout << "Shortest path is from robot starting at location " << I3 << std::endl;
//        }
//    }

    return 0;
}
//int main() {
//    ios::sync_with_stdio(0);
//    cin.tie(0);
//#ifdef DEBUG
////    freopen("output.txt", "w", stdout);
//#endif
//    solve();
//    return 1;
//}
//