5 контест я

// 1 задача
#include <iostream>
#include <vector>

using namespace std;

struct edge {
    int fr, to, weight;

    edge(int _fr = 0, int _to = 0, int _weight = 0) {
        fr = _fr;
        to = _to;
        weight = _weight;
    }
};

vector<edge> g;
const int INF = 1e9;
int n, m, k;

void ford_bellman(int v, int finish) {
    vector<int> d(n, INF);
    vector<int> d_(n, INF);
    d[v] = 0;
    for (int i = 0; i < k; i++) {
        for (int j = 0; j < m; j++) {
            if (d[g[j].fr] < INF) {
                d_[g[j].to] = min(d_[g[j].to], d[g[j].fr] + g[j].weight);
            }
        }
        d = d_;
    }
    if (d[finish] == INF) {
        cout << "-1";
    } else {
        cout << d[finish];
    }
}


int main() {
    int s, f;
    cin >> n >> m >> k >> s >> f;
    s--;
    f--;

    g = vector<edge>(m);

    for (int i = 0; i < m; i++) {
        int fr, to, weight;
        cin >> fr >> to >> weight;
        g[i].fr = fr - 1;
        g[i].to = to - 1;
        g[i].weight = weight;
    }

    ford_bellman(s, f);

    return 0;
}

// 2 задача
#include <iostream>
#include <vector>

using namespace std;

int n;
vector<vector<int>> graph;

void floidWarshall(){
    for (int k = 0; k < n; k++){
        for (int i = 0; i < n; i++){
            for (int j = 0; j < n; j++){
                graph[i][j] = min(graph[i][j], graph[i][k] + graph[k][j]);
            }
        }
    }
}

int main() {
    cin >> n;
    graph = vector<vector<int>> (n, vector<int>(n));
    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            cin >> graph[i][j];
        }
    }

    floidWarshall();

    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            cout << graph[i][j] << ' ';
        }
        cout << '\n';
    }
    return 0;
}