Go: package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := make(map[int]int)
	q[0] = 0
	visited := make(map[int]struct{})
	out := make([]int, n)

	for len(q) > 0 {
		u := top(q)
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			if d, ok := q[uu]; !ok || d > q[u]+c {
				q[uu] = q[u] + c
			}
		}

		out[u] = q[u]
		delete(q, u)
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

func top(q map[int]int) int {
	minu := -1
	min := -1
	for u, d := range q {
		if min < 0 || d < min {
			minu = u
			min = d
		}
	}

	return minu
}

C++: #include <iostream>
#include<cstdio>
using namespace std;
const int INF = (1 << 21);
static int G[100][100];

void AskSSSP(int n){
    
    const int BLACK = 2,GRAY = 1,WHITE =  0;
    int color[n],d[n];
    for(int i = 0;i < n;++i){
        d[i] = INF;
        color[i] = WHITE;
    }
    d[0] = 0;
    int min,u;
    while(1){
        int min = INF;
        for(int i=0;i < n;++i){
            if(color[i] != BLACK && d[i] < min){
                min = d[i];
                u = i;
            }
        }
        if(min == INF) break;
        color[u] = BLACK;
        for(int i=0;i < n;++i){
            if(color[i] != BLACK && G[u][i] != INF){
                if(d[u] + G[u][i] < d[i]){
                    d[i] = d[u] + G[u][i];
                    color[i] = GRAY;
                }
            }
        }
        
    }
    for(int i = 0;i < n;++i) printf("%d %d\n",i,d[i]);

}

int main(void){
    int n,t,k,v,u;
    scanf("%d",&n);
    for(int i = 0;i < n;++i){
        for(int j = 0;j < n;++j){
            G[i][j] = INF;
        }
    }
    for(int i = 0;i < n;++i){
        scanf("%d %d",&t,&k);
        for(int j = 0;j < k;j++){
            scanf("%d %d",&v,&u);
            G[t][v] = u;
        }
    }
    AskSSSP(n);
    
}

C++: #include <bits/stdc++.h>
using namespace std;
#define inf 1e9+100

int n, m, u, k, v, c;
pair<int,pair<int,int> > e[10000];

// sからtに辿り着くまでに閉路が存在すればtrueを返す
// グラフに閉路が存在してもそこを経由できない場合は閉路を検出しない
bool bford(int n, pair<int,pair<int,int> > *e, int *d, int s, int t = -1) {
	fill(d, d+n, inf), d[s] = 0;
	for (int i=0; i<n*2; ++i) {
		for (int j=0; j<m; ++j) {
			int from = e[j].first, to = e[j].second.first, cost = e[j].second.second;
			if(d[from]!=inf && d[to]>d[from]+cost){
				d[to] = d[from] + cost;
				if(to==t && n-1<=i) return true;
			}
		}
	}
	return false;
}

int main() {
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> u >> k;
		for (int j = 0; j < k; ++j) {
			cin >> v >> c;
			e[m++] = {u, {v, c}};
		}
	}
	int d[100];
	if (bford(n,e,d,0)) cout << -1 << endl;
	else for (int i=0; i<n; ++i) cout << i << ' ' << d[i] << endl;
}

C++: // clang-format off
#include <bits/stdc++.h>
#define int long long
#define main signed main()
#define loop(i, a, n) for (int i = (a); i < (n); i++)
#define rep(i, n) loop(i, 0, n)
#define forever while (true)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define prec(n) fixed << setprecision(n)
template<typename A> using V = std::vector<A>;
template<typename A> using F = std::function<A>;
template<typename A, typename B> using P = std::pair<A, B>;
using pii = P<int, int>;
using vi = V<int>;
using vd = V<double>;
using vs = V<std::string>;
using vpii = V<pii>;
using vvi = V<vi>;
using vvpii = V<vpii>;
constexpr int INF = sizeof(int) == sizeof(long long) ? 1000000000000000000LL : 1000000000;
constexpr int MOD = 1000000007;
constexpr double PI = acos(-1);
template<typename A, typename B> bool cmin(A &a, const B &b) { return a > b ? (a = b, true) : false; }
template<typename A, typename B> bool cmax(A &a, const B &b) { return a < b ? (a = b, true) : false; }
template<typename T> std::istream &operator>>(std::istream &is, std::vector<T> &v) { for (T &x : v) is >> x; return is; }
using namespace std;
// clang-format on

using Weight = int;
struct Edge {
  int src, dst;
  Weight weight;
  Edge(const int &s = 0, const int &d = 0, const Weight &w = 0) : src(s), dst(d), weight(w) {}
};

using Edges = std::vector<Edge>;
using Array = std::vector<Weight>;
using Matrix = std::vector<Array>;

class Graph {
  std::vector<Edges> g;

public:
  Graph(const int &size = 0) : g(size) {}

  void addArc(const int &src, const int &dst, const Weight &w = 1) { g[src].emplace_back(src, dst, w); }

  void addEdge(const int &node1, const int &node2, const Weight &w = 1) {
    addArc(node1, node2, w);
    addArc(node2, node1, w);
  }

  const Edges &operator[](const int &i) const { return g[i]; }

  Graph toRootedTree(int r);
  std::pair<std::vector<Weight>, std::vector<int>> dijkstra(const int &src, const int &inf);
  Matrix warshallFloyd(const int &inf);
  std::pair<Weight, Edges> prim(const int &r);
  template<typename UnionFind> std::pair<Weight, Edges> kruskal();
  Weight solveTSP(const int &inf);
};

std::pair<std::vector<Weight>, std::vector<int>> Graph::dijkstra(const int &src, const int &inf = std::numeric_limits<Weight>::max() / 8) {
  using state = std::pair<Weight, int>;
  std::priority_queue<state, std::vector<state>, std::greater<state>> q;
  std::vector<Weight> dist(g.size(), inf);
  std::vector<int> via(g.size());
  dist[src] = 0;
  q.emplace(0, src);
  while (q.size()) {
    Weight d;
    int v;
    std::tie(d, v) = q.top();
    q.pop();
    if (dist[v] < d) continue;
    for (auto &e : g[v]) {
      if (cmin(dist[e.dst], dist[v] + e.weight)) {
        via[e.dst] = v;
        q.emplace(dist[e.dst], e.dst);
      }
    }
  }
  return {dist, via};
}

main {
  int n;
  cin >> n;
  Graph g(n);
  rep(_, n) {
    int u, k;
    cin >> u >> k;
    while (k--) {
      int v, c;
      cin >> v >> c;
      g.addArc(u, v, c);
    }
  }
  vi d = g.dijkstra(0).first;
  rep(i, n) cout << i << ' ' << d[i] << endl;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1 << 20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int>> adj[MAX];

void dijkstra() {
	priority_queue<pair<int, int>> PQ;
	int color[MAX];
	int d[MAX];
	for (int i = 0; i < n; i++) {
		d[i] = INFTY;
		color[i] = WHITE;
	}

	d[0] = 0;
	PQ.push(make_pair(0, 0));
	color[0] = GRAY;

	while (!PQ.empty()) {
		pair<int, int> f = PQ.top(); PQ.pop();
		int u = f.second;
		color[u] = BLACK;

		if (d[u] < f.first*(-1)) continue;

		for (unsigned int j = 0; j < adj[u].size(); j++) {
			int v = adj[u][j].first;
			if (color[v] == BLACK) continue;
			if (d[v] > d[u] + adj[u][j].second) {
				d[v] = d[u] + adj[u][j].second;
				PQ.push(make_pair(d[v] * (-1), v));
				color[v] = GRAY;
			}
		}
	}

	for (int i = 0; i < n; i++) {
		cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
	}
}

int main() {
	int k, u, v, c;

	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v >> c;
			adj[u].push_back(make_pair(v, c));
		}
	}

	dijkstra();

	return 0;
}