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<algorithm>
#include<queue>
#define inf 200000000
#define Max 10000
#define W 0
#define G 1
#define B 2
using namespace std;
vector<pair<int,int>> g[Max];
int n,d[Max];
void dikstr(int s){
	int color[Max];
int i,j;
	pair<int,int> u;
	priority_queue<pair<int,int>> PQ;
	for(i=0;i<n;i++){
	color[i]=W;
		d[i]=inf;
	}
	d[s]=0;
	PQ.push(make_pair(s,0));
	color[s]=G;
	while(!PQ.empty()){
		u=PQ.top();PQ.pop();
		int uf=u.first,us=u.second;
		color[us]=B;
		if(d[us]<uf*(-1))
		continue;
		
		for( j=0;j<g[us].size();j++){
			int v=g[us][j].first;
			if(color[v]!=B){
				if(d[us]+(g[us][j].second)<d[v]){
					d[v]=d[us]+(g[us][j].second);
					color[v]=G;
					PQ.push(make_pair(d[v]*(-1),v));
				}
			}
		}
	}
	
	
}

main(){
	int u,k,v,c;
	scanf("%d",&n);
	int i,j;
	for(i=0;i<n;i++){
		scanf("%d%d",&u,&k);
		for(j=0;j<k;j++){
			scanf("%d%d",&v,&c);
			g[u].push_back(make_pair(v,c));
		}
	}
	dikstr(0);
	for(i=0;i<n;i++){
		printf("%d %d\n",i,d[i]);
	}
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
#include <vector>

using namespace std;

const int MAX=10000;
const int INFTY=(1<<21);
const int WHITE=0;
const int GRAY=1;
const int BLACK=2;

vector<pair<int, int> > adj[MAX];
int n;

void dijkstra(){
    priority_queue<pair<int, int> > PQ;
    int color[MAX],d[MAX];

    for(int i=0;i<n;i++){
        d[i]=INFTY;
        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]==INFTY ? -1:d[i])<<endl;
    }

    return;
}

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

    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();

}

C++: #include <stdio.h>

int a,b, c,n,u,w[10000][10000],color[10000],d[10000];

int main(){
  int i,j,mincost,sum=0;
  scanf("%d",&n);
 for(i=0;i<n;i++)
   for(j=0;j<n;j++)w[i][j]=100008;

  for(i=0;i<n;i++){
    scanf("%d%d",&a,&c);
      for(j=0;j<c;j++){
scanf("%d",&b);
 scanf("%d",&w[a][b]);    
}
    }
 
  for(i=0;i<n;i++){
    d[i] =100008;
    color[i] =0;
  }
  d[0]=0;

  while (1){
    mincost=100008;    
for(i=0;i<n;i++){
      if (color[i] != 1 && d[i] < mincost){
	mincost = d[i];
	u = i;
      }
    }
    if (mincost ==100008)
      break;
    color[u] = 1;
    for (i=0;i<n;i++){
      if (color[i] != 1 && d[u]+w[u][i] < d[i]){
	d[i] = d[u]+w[u][i];
      }
    }
  }
 
 for (i=0;i<n;i++)
 printf("%d %d\n",i,d[i]); 

  return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cassert>
#include <string>
#include <cstring>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <algorithm>

using namespace std;

// ---------------------
// repetition
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)

// debug
#define dump(x)  cerr << #x << " = " << (x) << endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

// ---------------------
#define INF (1 << 21)
typedef long long ll;

int main() {
  int n;
  cin >> n;

  vector<int> V[n];
  int E[n][n];
  int d[n];
  int visited[n];

  REP(x, n) {
    REP(y, n) {
      E[x][y] = INF;
    }
    d[x] = INF;
    visited[x] = 0;
  }

  REP(_, n) {
    int u, k;
    cin >> u >> k;
    REP(__, k) {
      int v, c;
      cin >> v >> c;
      V[u].push_back(v);
      E[u][v] = c;
      // E[v][u] = c;
    }
  }

  d[0] = 0;
  REP(_, n) {
    int minv = -1;
    int mincost = INF;
    REP(v, n) {
      if (!visited[v] && d[v] < mincost) {
        minv = v;
        mincost = d[v];
      }
    }
    visited[minv] = 1;
    for (vector<int>::iterator it = V[minv].begin(); it != V[minv].end(); it++) {
      if (E[minv][*it] < INF && d[minv] + E[minv][*it] < d[*it]) {
        d[*it] = d[minv] + E[minv][*it];
      }
    }
  }

  REP(i, n) {
    cout << i << " " << d[i] << endl;
  }
  return 0;
}