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>
using namespace std;
#include<queue>
#include<vector>
#include<string>
#include<string.h>
#include<algorithm>
bool b[2003];

#define REP(i, a) for(int i=0;i<a;i++)
	int N=10000000;
int main()
{
	pair<int,int> f;
	vector < pair<int,int> > A[10001];
	priority_queue < pair < int,int > > PQ;
	int min,b,a,k,m,n ,e,p[101],d[101],u,v; //u ?????????v????????¨
	bool color[10001];

	cin>>n;
	REP(i, n) {
		cin>>u>>k;
		REP(i, k) {
			cin>>a>>b;
			if(b==-1) b=N;
			A[u].push_back(make_pair(a,b));
		}
		color[i]=0;
		d[i]=N;
	}
	a=0;
	d[0]=0;
	PQ.push(make_pair(0,0));
	while(!PQ.empty()){
		f=PQ.top();
		PQ.pop();
		u=f.second;
		color[u]=1;
		REP(i,A[u].size()){
			v=A[u][i].first;
			if(color[v]==1){
			continue;
			}
				if(d[v]>A[u][i].second+d[u]){
					d[v]=A[u][i].second+d[u];
					PQ.push(make_pair(d[v]*-1,v));
				}
		}
	}
	REP(i,n){
		cout<<i<<" "<<(d[i] == N ? -1 : d[i])<<endl;
	
	}
	return 0;
}

C++: #include<iostream>
#include<climits>
using namespace std;

typedef struct{
  int A[10010];
  long long ans;
  bool c;
}node;
node T[10010];
int Q[100000003];
int head=0;
int tail=1;
int n;

void function(int num){
  while(true){
    if(head==tail)break;
    num=Q[head++];
    if(head==99999999)head=1;
    T[num].c=true;
    for(int i=0;i<n;i++){
      if(T[num].A[i]!=0){
	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==99999999)tail=1;
	}
      }
    }
  }
}

int main(){
  int num,son,z,w;
  cin>>n;
  for(int i=0;i<n;i++){
    cin>>num>>son;
    T[num].ans=LONG_LONG_MAX;
    for(int j=0;j<son;j++){
      cin>>z>>w;
      T[num].A[z]=w;
      }
  }
  Q[0]=0;
  T[0].ans=0;
  function(0);
 
  for(int i=0;i<n;i++){
      cout<<i<<" "<<T[i].ans<<endl;
  }
  return 0;
}

C++: #include<algorithm>
#include<iostream>
//#include<cstdlib>
//#include<cstring>
//#include<cstdio>
//#include<vector>
#include<queue>
//#include<stack>
//#include<cmath>
//#include<list>
//#include<map>
//#include<set>
using namespace std;

//typedef vector<int> VI;
//typedef vector<VI> VVI;
//typedef vector<string> VS;
//typedef stack<int> SI;
//typedef queue<int> QI;
//typedef pair<int,int> PII;
//typedef long long LL;

//#define d(x)  cout<<#x<<" = "<<(x)<<endl;
//#define ALL(a)  (a).begin(),(a).end()
//#define RALL(a) (a).rbegin(), (a).rend()
//#define PB push_back
//#define MP make_pair
//#define EMP empty()
//#define SZ(a) int((a).size())
//#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
//#define REACH(i,c) for(typeof((c).rbegin()) i=(c).rbegin(); i!=(c).rend(); ++i)
//#define EXIST(s,e) ((s).find(e)!=(s).end())
//#define SORT(c,n) sort(c,c+n)
//#define VSORT(c) sort((c).begin(),(c).end())
//#define FOR(i,a,b) for(int i=(a);i<(b);++i)
//#define REP(i,n)  FOR(i,0,n)
//#define DFOR(i,b,a) for(int i=(b)-1;i>=(a);--i)
//#define DREP(i,n) DFOR(i,n,0)
//#define INF 1000000000

//const double EPS = 1e-10;
//const double PI  = acos(-1.0);
////////////////////////////////////////////////
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()
{
	priority_queue<pair<int,int>> PQ;
	int color[MAX];
	int d[MAX];
	for(int i=0;i<n;i++)
	{
		d[i]=INF;
		color[i]=WHITE;
	}
	
	d[0]=0;
	PQ.push(make_pair(0,0));
	color[0]=GRAY;
	
	while(!PQ.empty())
	{
		PII f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=BLACK;
		
		if(d[u]<f.first*(-1))continue;
		
		for(int j=0;j<SZ(adj[u]);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]==INF?-1:d[i])<<endl;
	}
}

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