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<climits>
#include<cstdio>
using namespace std;

typedef struct{
  int A[10001];
  int ans;
}node;

int head=0;
int tail=1;
int n;


int main(){
  int num,son,z,w;
  cin>>n;
  node *T=new node[n];
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      T[i].A[j]=-1;
    }
  }

  for(int i=0;i<n;i++){
    scanf("%d%d",&num,&son);
    T[num].ans=INT_MAX;
    for(int j=0;j<son;j++){
      scanf("%d%d",&z,&w);
      T[num].A[z]=w;
      }
  }

  T[0].ans=0;

  int *Q=new int[1000000];
  Q[0]=0;
  while(true){
    if(head==tail)break;
    num=Q[head++];
    //if(head==n*5-1)head=1;
    for(int i=0;i<n;i++){
      if(T[num].A[i]!=-1){
	if(T[i].ans>T[num].ans+T[num].A[i]){
	  T[i].ans=T[num].ans+T[num].A[i];
	  Q[tail++]=i;
	  //if(tail==n*5-1)tail=1;
	}
      }
    }
  }
  delete [] Q;
 
  for(int i=0;i<n;i++){
      cout<<i<<" "<<T[i].ans<<endl;
  }
  delete [] T;
  return 0;
}

C++: #include<iostream>
#include<queue>
#include<algorithm>
#include<functional>
#define MAX 10000
#define INFTY (1<<20)
#define MPII(a,b) make_pair((a),(b))
#define PII pair<int,int>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) for(int i=0;i<(n);i++)
using namespace std;

class Node
{
public:
	Node() {};
	int d;
	bool done;
	priority_queue<PII, vector<PII>, greater<PII>> E;
};

int main()
{
	priority_queue<PII, vector<PII>, greater<PII>> order;
	Node nodes[MAX];
	REP(i, MAX)
	{
		nodes[i].done = false;
		nodes[i].d = INFTY;
	}
	int n;
	cin >> n;
	FOR(i, 0, n)
	{
		int ID, m;
		cin >> ID >> m;
		REP(l, m)
		{
			int v, w;
			cin >> v >> w;
			PII p = MPII(w, v);
			nodes[ID].E.push(p);
		}
	}
	PII now = MPII(0, 0);
	order.push(now);
	nodes[now.second].d = 0;
	while (1)
	{
		if (!nodes[now.second].done)
		{
			while (!nodes[now.second].E.empty())
			{
				PII temp = nodes[now.second].E.top();
				nodes[now.second].E.pop();
				int nextv = temp.second;
				int w = temp.first;
				if (nodes[nextv].d > nodes[now.second].d + w)
				{
					nodes[nextv].d = nodes[now.second].d + w;
				}
				order.push(MPII(nodes[nextv].d,nextv ));
			}
			nodes[now.second].done = true;
		}
		order.pop();
		if (order.empty())break;
		now = order.top();
	}
	REP(i, n)
	{
		cout << i << " " << nodes[i].d << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#include <functional>
#include <string.h>

using namespace std;
static const int INF = 2e9;
static const int SIZE = 10001;
typedef pair<int, int> P;
struct edge
{
	int to;
	int cost;
};

int d[SIZE];
vector<edge> G[SIZE];

void solve()
{
	int n;
	cin >> n;
	for (int i = 0; i < n; ++i)
	{
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; ++j)
		{
			int to, cost;
			scanf("%d %d", &to, &cost);
//			cin >> to >> cost;
			edge e1;
			e1.to = to;
			e1.cost = cost;
			G[u].push_back(e1);
		}
	}
	for (int i = 0; i < SIZE; ++i)
	{
		d[i] = INF;
	}
	d[0] = 0;
	priority_queue<P, vector<P>, greater<P> > pque;
	pque.push(P(0, 0));
	while (!pque.empty())
	{
		P p = pque.top();
		pque.pop();
		int v = p.second;
		for (int i = 0; i < G[v].size(); ++i)
		{
			edge e = G[v][i];
			if (d[e.to] > d[v] + e.cost)
			{
				d[e.to] = d[v] + e.cost;
				pque.push(P(d[e.to], e.to));
			}
		}
	}
	for (int i = 0; i < n; ++i)
	{
		printf("%d %d\n", i, d[i]);
//		cout << i << " " << d[i] << endl;
	}
}

int main()
{
	solve();
	return(0);
}