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<stdio.h>
#include<queue>
#include<string.h>
using namespace std;
#define INF 1 << 30
struct ss{
	int next;
	int to;
	int val;
}e[200050];
int head[200050];
int tot;
void add(int x,int y,int val){
	e[tot].next=head[x];
	e[tot].to=y;
	e[tot].val=val;
	head[x]=tot++;
}
int n;
int vis[200000];
int dis[200050];
void spfa(){
	for(int i=0;i<n;i++){
		dis[i]=INF;
	}
	vis[0]=1;
	dis[0]=0;
	queue<int> st;
	st.push(0);
	while(!st.empty()){
		int t=st.front();
		st.pop();
		vis[t]=0;
		for(int i=head[t];i!=-1;i=e[i].next){
			int to=e[i].to;
			if(dis[to]>dis[t]+e[i].val){
				dis[to]=dis[t]+e[i].val;
				if(!vis[to]){
					st.push(to);
					vis[to]=1;
				}
			}
		}
	}
}
int main(){
	scanf("%d",&n);
	tot=0;
	memset(head,-1,sizeof(head));
	int a,to,val,num;
	for(int i=0;i<n;i++){
		scanf("%d %d",&a,&num);
		for(int j=1;j<=num;j++){
			scanf("%d %d",&to,&val);
			add(a,to,val);
		}
	}
	spfa();
	printf("0 0\n");
	for(int i=1;i<n;i++){
		printf("%d %d\n",i,dis[i]);
	}
	return 0;
}

C++: #include<cstdio>
#include<iostream>
#include<queue>
#include<algorithm>
#define Lens 10005
#define Inf 1<<22

using namespace std;
vector<pair<int, int> > adj[Lens];
int N;
char c[Lens];
int d[Lens];

void dijkstra()
{
	d[0] = 0;
	priority_queue<pair<int, int> > PQ;
	PQ.push(make_pair(0, 0));
	while (!PQ.empty())
	{
		pair<int, int> t = PQ.top();
		PQ.pop();
		int u = t.second;
		c[u] = 'b';
		if (d[u] < -t.first) continue;
		for (int i = 0; i < adj[u].size(); i++)
		{
			int tmp = adj[u][i].first;
			if (c[tmp] == 'w'&&d[tmp] > d[u] + adj[u][i].second)
			{
				d[tmp] = d[u] + adj[u][i].second;
				PQ.push(make_pair(-d[tmp],tmp));
				cout << tmp << "  " << d[tmp] << endl;
			}
		}

	}
}

int main()
{

	cin >> N;
	for (int i = 0; i < N; i++)
	{
		int k, n;
		cin >> k >> n;
		c[k] = 'w';
		d[k] = Inf;
		for (int j = 0; j < n; j++)
		{
			int v, tw;
			cin >> v >> tw;
			adj[k].push_back(make_pair(v, tw));
		}

	}
	dijkstra();
	for (int i = 0; i < N; i++)
	{
		cout << i << ' ' << d[i] << endl;;
	}
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<vector>
#include<utility>
#include<limits>
using namespace std;
typedef pair<int, int> Edge;
int main()
{
	int n; cin >> n;
	vector< vector< Edge > > lists;

	for (int i = 0; i < n; i++)
	{
		vector<Edge> list;
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; j++)
		{
			Edge edge;
			cin >> edge.second >> edge.first;
			list.push_back(edge);
		}
		lists.push_back(list);
	}

	vector<int> costs(n, -1);
	costs[0] = 0;
	priority_queue<Edge> queue;
	queue.push(Edge(0, 0));

	while (!queue.empty())
	{
		Edge edge = queue.top(); queue.pop();
		int dest = edge.second;
		int cost = edge.first;
		if (costs[dest]<cost)continue;
		for (Edge next : lists[dest])
		{
			next.first += cost;
			if (costs[next.second] > next.first||costs[next.second]==-1)
			{
				costs[next.second] = next.first;
				queue.push(next);
			}
		}
	}
	for (int i = 0; i < n; i++)
		cout << i << " " << costs[i] << endl;

	char c;
	cin >> c;

	return 0;
}