Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
const INF = 1 << 60

type Edge struct {
	to, cost int
}

type Node struct {
	id, cost int
}

type PQ []Node

func (pq PQ) Len() int           { return len(pq) }
func (pq PQ) Less(i, j int) bool { return pq[i].cost < pq[j].cost }
func (pq PQ) Swap(i, j int)      { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PQ) Push(x interface{}) {
	*pq = append(*pq, x.(Node))
}

func (pq *PQ) Pop() interface{} {
	old := *pq
	n := len(old)
	x := old[n-1]
	*pq = old[0 : n-1]
	return x
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		E[id] = make([]Edge, k)
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id][j] = Edge{to, cost}
		}
	}

	d := make([]int, N)
	for i := 0; i < N; i++ {
		d[i] = INF
	}
	done := make([]bool, N)
	pq := &PQ{}
	heap.Init(pq)
	d[0] = 0
	heap.Push(pq, Node{0, 0})
	for pq.Len() > 0 {
		cur := heap.Pop(pq).(Node).id
		if done[cur] {
			continue
		}
		done[cur] = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+d[cur]
			if !done[to] && cost < d[to] {
				d[to] = cost
				heap.Push(pq, Node{to, cost})
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, d[i])
	}
	wtr.Flush()
}

C++: #include <iostream>
#include <vector>
#include <queue>
#include <climits>

struct Node {
	int id;
	std::vector<int> edge_to;
	std::vector<int> edge_cost;
	bool done;
	int cost;
};

bool operator>(const Node& u, const Node& v) { return u.cost > v.cost; }
bool operator<(const Node& u, const Node& v) { return u.cost < v.cost; }
bool operator>=(const Node& u, const Node& v) { return u.cost >= v.cost; }
bool operator<=(const Node& u, const Node& v) { return u.cost <= v.cost; }
bool operator==(const Node& u, const Node& v) { return u.id == v.id; }
bool operator!=(const Node& u, const Node& v) { return u.id != v.id; }

void swap(int& x, int& y)
{
	int tmp = x;
	x = y;
	y = tmp;
}

int min(int x, int y)
{
	return x>y ? y : x;
}

int main()
{
	int n; std::cin >> n;
	
	Node* nodes = new Node[n];
	
	for (int i=0; i<n; i++) {
		nodes[i].done = false;
		nodes[i].cost = INT_MAX;
	}
	
	for (int i=0; i<n; i++) {
		int id, deg;
		std::cin >> id >> deg;
		nodes[i].id = id;
		for (int j=0; j<deg; j++) {
			int t, cost;
			std::cin >> t >> cost;
			nodes[i].edge_to.push_back(t);
			nodes[i].edge_cost.push_back(cost);
		}
	}
	
	std::priority_queue<Node, std::vector<Node>, std::greater<std::vector<Node>::value_type>> que;
	que.push(nodes[0]);
	nodes[0].cost = 0;
	
	while (!que.empty()) {
		Node v = que.top(); que.pop();
		int s = v.id;
		// std::cout << s << " " << nodes[s].cost << std::endl;
		nodes[s].done = true;
		for (int k=0; k<nodes[s].edge_to.size(); k++) {
			int t = nodes[s].edge_to[k];
			int cost = nodes[s].edge_cost[k];
			if (nodes[t].done) continue;
			if ( nodes[t].cost > nodes[s].cost + cost) {
				nodes[t].cost = nodes[s].cost + cost;
				que.push(nodes[t]);
			}
		}
	}
	
	for (int i=0; i<n; i++) {
		std::cout << nodes[i].id << " " << nodes[i].cost << std::endl;
	}
	
	delete[] nodes;
	
	return 0;
}

C++: #include<iostream>
#include<vector>
#include<queue>
#include<utility>
#include<climits>
#include<algorithm>
using namespace std;
typedef int Cost;
typedef int Node;

void dijkstra(int start,   vector<vector< pair<Node,Cost> > > m){
  vector<Cost> costs(m.size());
  bool visited[m.size()];

  fill(costs.begin(),costs.end(),INT_MAX);
  fill(visited,visited+m.size(),false);
  
  priority_queue<pair<Cost,Node> ,vector<pair<Cost,Node> >, greater<pair<Cost,Node> > > q;
  q.push(make_pair(0,start));
  while(!q.empty()){
    Cost c = q.top().first;
    Node n = q.top().second;
    q.pop();
    if(!visited[n]){
      costs[n] = c;
      for(auto &x:m[n]){
        int node = x.first;
        int cost = x.second;
        q.push(make_pair(cost+c,node));
      }
      visited[n] = true;
    }
  }
  for(int i = 0;i < costs.size();i++){
    cout << i << ' ' << costs[i] << endl;
  }
}

int main(){
  int n;
  cin >> n;
  vector<vector< pair<Node,Cost> > > m(n);
  
  for(int i = 0;i < n;i++){
    int u,k;
    cin >> u >> k;
    for(int j = 0;j < k;j++){
      int v,c;
      cin >> v >> c;
      m[u].push_back(make_pair(v,c));
    }
  }
  dijkstra(0,m);
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX=10000;
static const int INF=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(){
	int color[n];
	int d[n];
	for(int i=0;i<n;i++){
		color[i]=WHITE;
		d[i]=INF;
	}

	d[0]=0;
	priority_queue<pair<int,int> > pq;
	pq.push(make_pair(0,0));
	
	while(!pq.empty()){
		pair<int,int> f=pq.top();pq.pop();
		int u=f.second;
		color[u]=BLACK;
		
		int size=adj[u].size();
		for(int j=0;j<size;j++){
			int v=adj[u][j].first;
			if(color[v]==BLACK) continue;
			int w=adj[u][j].second;
			if(d[v]>d[u]+w){
				d[v]=d[u]+w;
				pq.push(make_pair(d[v]*-1,v));
			}
		}
	}

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

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