Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s) {
	for (int i = 0; i < V; i++) {
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;
	while (true) {
		int v = -1;
		for (int u = 0; u < V; u++) {
			if (!used[u] && ((v == -1) || d[u] < d[v])) {
				v = u;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		used[v] = true;
		for (int u = 0; u < V; u++) {
			if (cost[v][u] != -1) {
				d[u] = min(d[u], d[v] + cost[v][u]);
			}
		}
	}
}

int main() {
	for (int i = 0; i < MAX_V; i++) {
		for (int j = 0; j < MAX_V; j++) {
			cost[i][j] = -1;
		}
	}
	cin >> V;
	for (int i = 0; i < V; i++) {
		int u;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;
		}
	}
	dijkstra(0);

	for (int i = 0; i < V; i++) {
		cout << i << " " << d[i] << endl;
	}
	return 0;
}

C++: #include <stdio.h>
#include <iostream>
#include <queue>
using namespace std;

class Vertice;
class Edge;

class Vertice{
private:
	int id;
	int edge_num;
	int *vertice_id_list;
	Edge **edges;
	bool flag_fixed;
	int distance_min;
public:
	Vertice(int id, int edge_num_max);
	~Vertice(){ delete[] edges, vertice_id_list; }
	int getDistanceMin() const { return distance_min; }
	void addEdge(int vertice_id, Edge *edge);
	void addVertices(Vertice *vertices[]);
	void setDistance(int d);
	void serveDistance();
	void setFlagFixed(){ flag_fixed = true; }
};

class Edge{
private:
	int distance;
	Vertice *vertice;
public:
	Edge(int distance){ this->distance = distance; }
	void addVertice(Vertice *vertice){ this->vertice = vertice; }
	void setDistance(int distance){ vertice->setDistance(distance + this->distance); }
};

struct verticeComp {
	bool operator()(const Vertice *v1, const Vertice *v2)
	{
		return v1->getDistanceMin() > v2->getDistanceMin();
	}
};

priority_queue<Vertice*, vector<Vertice*>, verticeComp> PQ; 

Vertice::Vertice(int id, int edge_num_max)
{
	this->id = id;
	edge_num = 0;
	vertice_id_list = new int[edge_num_max];
	edges = new Edge*[edge_num_max];
	flag_fixed = false;
	distance_min = 1000000;
}

void Vertice::addEdge(int vertice_id, Edge *edge)
{
	edges[edge_num] = edge;
	vertice_id_list[edge_num] = vertice_id;
	edge_num++;
}

void Vertice::addVertices(Vertice *vertices[])
{
	for (int i = 0; i < edge_num; i++) {
		edges[i]->addVertice(vertices[vertice_id_list[i]]);
	}
}

void Vertice::setDistance(int d)
{
	if (flag_fixed) return;
	if (d < distance_min) distance_min = d;
	PQ.push(this);
}

void Vertice::serveDistance()
{
	for (int i = 0; i < edge_num; i++) {
		edges[i]->setDistance(distance_min);
	}
	if (PQ.empty()) return;
	Vertice *fixed_vertice = PQ.top();
	PQ.pop();
	fixed_vertice->setFlagFixed();
	fixed_vertice->serveDistance();
}

int main(void)
{
	Vertice **vertices;

	int n;
	cin >> n;
	vertices = new Vertice*[n];cout << "wa1" << endl;
	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		vertices[u] = new Vertice(u, k);
		for (int j = 0; j < k; j++) {
			int v, c;
			cin >> v >> c;
			vertices[u]->addEdge(v, new Edge(c));
		}
	}cout << "wa2" << endl;

	for (int i = 0; i < n; i++) {
		vertices[i]->addVertices(vertices);
	}cout << "wa3" << endl;

	vertices[0]->setDistance(0);cout << "wa4" << endl;
	vertices[0]->setFlagFixed();cout << "wa41" << endl;
	PQ.pop();cout << "wa42" << endl;
	vertices[0]->serveDistance();cout << "wa5" << endl;

	for (int i = 0; i < n; i++) {
		cout << i << " ";
		cout << vertices[i]->getDistanceMin() << endl;
	}cout << "wa6" << endl;

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n); i >= 0; i--)
#define REP(i, m, n) for (int i = (int)(m); i <= (int)(n); i++)
#define REPR(i, m, n) for (int i = (int)(m); i >= (int)(n); i--)
#define all(v) v.begin(), v.end()
typedef long long ll;
const int INF = 1001001001;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using Graph = vector<vector<int> >;

int n;
vector<bool> seen;
vector<int> dist;
priority_queue<pair<int, int> > pq;

void dijkstra(const Graph &G, int v){
  seen[v] = true;

  rep(u, n){
    if(G[v][u] == -1) continue;
    if(seen[u] == true) continue;
    if(chmin(dist[u], dist[v]+G[v][u])) pq.push(make_pair((-1)*dist[u], u));
  }

  while(!pq.empty()){
    pair<int, int> tmp;
    tmp = pq.top();
    pq.pop();
    if(seen[tmp.second]) continue;
    int nv = tmp.second;
    dijkstra(G, nv);
  }

  return;
}

int main(){
  cin >> n;

  Graph G(n, vector<int>(n, -1));
  rep(i, n){
    int v, k; cin >> v >> k;
    rep(j, k){
      int u, c; cin >> u >> c;
      G[v][u] = c;
    }
  }

  seen.assign(n, false);
  dist.assign(n, INF);
  dist[0] = 0;
  dijkstra(G, 0);

  rep(i, n) cout << i << " " << dist[i] << endl;

  return 0;
}