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<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())
	{
		pair<int,int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=BLACK;
		
		if(d[u]<f.first*(-1))continue;
		
		for(int j=0;j<adj[u].size();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;
}

C++: #include<iostream>
#include<cstdio>
#define INF 1<<30
#define FinishFunction return 0
#define MAX 1000000
using namespace std;
        
struct edge {
  int from,to,cost,k;
};
      
edge es[MAX];
      
int main(){
  int n,u,k,E,c,v;
  E = 0;
  scanf("%d",&n);
      
  for(int i=0;i<n;i++){
    scanf("%d %d",&u,&k);
         
    for(int j=0;j<k;j++){
      scanf("%d %d",&v,&c);
      es[E].from = u;
      es[E].to = v;
      es[E++].cost = c;
    }
  }
      
  // Ika berumanfo-do
  int d[MAX];
  for(int i=0;i<n;i++)d[i] = INF;
  d[0] = 0;
  while(true){
    bool update = false;
    for(int i=0;i<E;i++){
      edge e = es[i];
      if(d[e.from] != INF && d[e.to] > d[e.from] + e.cost){
    d[e.to] = d[e.from] + e.cost;
    update = true;
      }
    }
    if(!update)break;
  }
  for(int i=0;i<n;i++)cout << i << " " << d[i] << endl;
  FinishFunction;// return 0
}

C++: #include <bits/stdc++.h>
using namespace std;
#define MAX 10000
static const int INFTY = (1 << 20);
#define WHITE 0
#define BLACK 1

// グラフの頂点数
int n;
// 隣接リスト表現(第1成分は頂点番号、第2成分は辺の重み)
vector<vector<pair<int, int> > > G(MAX);
// 頂点のコストを記録する配列
vector<int> d(MAX, INFTY);
// 頂点の状態を記録する配列
vector<int> color(MAX, WHITE);

void dijkstra()
{
  // コストが小さいものを優先する優先度付きキュー
  // 第1成分は辺の重み*(-1)、第2成分は頂点番号
  priority_queue<pair<int, int> > PQ;
  // 初期化
  d.at(0) = 0;
  PQ.push(make_pair(0, 0));
  while (!PQ.empty())
  {
    pair<int, int> f = PQ.top();
    int v = f.second;
    PQ.pop();
    color.at(v) = BLACK;

    // 「余り物」の要素は無視する
    if (d.at(v) < f.first * (-1))
    {
      continue;
    }

    // vに隣接するV-Sの頂点uのdを更新する
    for (int i = 0; i < G.at(v).size(); i++)
    {
      int u = G.at(v).at(i).first;
      // 辺(v,u)の重み
      int cost = G.at(v).at(i).second;
      if (color.at(u) == WHITE)
      {
        // uがV-Sの頂点のとき
        if (d.at(v) + cost < d.at(u))
        {
          // uのdを更新する必要があるとき
          d.at(u) = d.at(v) + cost;
          PQ.push(make_pair(d.at(u) * (-1), u));
        }
      }
    }
  }
}

int main()
{
  cin >> n;
  for (int i = 0; i < n; i++)
  {
    int u, m;
    cin >> u >> m;
    for (int j = 0; j < m; j++)
    {
      int v, cost;
      cin >> v >> cost;
      G.at(u).push_back(make_pair(v, cost));
    }
  }

  dijkstra();

  for (int i = 0; i < n; i++)
  {
    cout << i << " " << d.at(i) << endl;
  }
}