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++: /*???????????????????????¢?????´???????????§?????????????°???¨??????????????????????????¢?´¢??????*/
/*????????????????????\????????¨???????????¨??§???????????????O((|E|+|V|)log|V|)?????§??????*/
#include <iostream>
#include <algorithm>
#include <queue>
#include <vector>
#define rep(i,n) for(int i=0;i<n;i++)
#define rep0(i,i0,n) for(int i = i0;i<=n;i++)
using namespace std;
#define inf (1<<20)
#define MAX 100000

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];
    rep(i, n){
        D[i]=inf;
        color[i]=inf;
    }
    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;

        rep(j, adj[u].size()){
            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;
            }
        }
    }

    rep (i,n) cout << i << " " << ( D[i] == inf ? -1 : D[i]) << endl;
}

int main(void){
    int k,u,v,c;
    cin >> n;

    rep(i, n){
        cin >> u >>k;
        rep(j, k){
            cin >> v >> c;
            adj[u].push_back(make_pair(v, c));
        }
    }

    Dijkstra();

    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll INF = 1000 * 100000;

int main(void){
  int n;
  cin >> n;
  vector< vector<pair<int, int> > > g(n);
  for(int i=0; i < n; i++){
    int v; cin >> v;
    int k; cin >> k;
    for(int j=0; j < k; j++){
      int v0, c; cin >> v0 >> c;
      g[v].push_back(make_pair(v0, c));
    }
  }
  vector<ll> d(n, INF);
  vector<bool> used(n, false);
  priority_queue<pair <int, int> > pq;
  d[0] = 0;

  pq.push(make_pair(0, 0));

  while(!pq.empty()){
    pair<int, int> f = pq.top(); pq.pop();
    int u = f.second;
    used[u] = true;
    if(d[u] < f.first * (-1)) continue;

    for(int i=0; i < g[u].size(); i++){
      int v = g[u][i].first;
      if(used[v] == true) continue;
      if(d[v] > d[u] + g[u][i].second){
        d[v] = d[u] + g[u][i].second;
        pq.push(make_pair(d[v] * (-1), v));
      }
    }
  }
  for(int i=0; i < n; i++){
    cout << i << " " << d[i] << endl;
  }

  return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define MAX 100
#define INF (1<<30)

using namespace std;
enum state{
  BLACK,
  WHITE
};

int main(){
  vector<int> v[MAX];
  vector<int> c[MAX];
  state s[MAX];
  int d[MAX];
  int n; cin>>n;

  for(int i=0;i<n;i++){
    int u; cin>>u;
    int k; cin>>k;
    for(int j=0;j<k;j++){
      int tmp,tmp2; cin>>tmp>>tmp2;
      v[u].push_back(tmp);
      c[u].push_back(tmp2);
    }
  }

  for(int i=0;i<n;i++){
    s[i] = WHITE;
    d[i] = INF;
  }
  s[0]=BLACK;
  d[0]=0;

  vector<int> blacklist;
  blacklist.push_back(0);

  while(1){
    int& last = blacklist.back();
    for(int i = 0;i<v[last].size();i++){
      if(d[v[last][i]]>d[last]+c[last][i]){
        d[v[last][i]]=d[last]+c[last][i];
      }
    }

    int minv=-1;
    int mind=INF;
    for(int b:blacklist){
      for(int i=0;i<v[b].size();i++){
        if(s[v[b][i]]!=BLACK && d[v[b][i]]<mind){
          minv=v[b][i];
          mind=d[v[b][i]];
        }
      }
    }
    if(minv!=-1){
      s[minv]=BLACK;
      blacklist.push_back(minv);
    }else{
      break;
    }
  }

  for(int i=0;i<n;i++){
    printf("%d %d\n",i,d[i]);
  }
}