Go: package main

import (
	"bufio"
	"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
type Node struct {
	cost int
	done bool
}

type Edge struct {
	to, cost int
}

const INF = 1 << 60

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	nodes := make([]Node, N)
	for i := 0; i < N; i++ {
		nodes[i].cost = INF
	}
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id] = append(E[id], Edge{to, cost})
		}
	}
	nodes[0].cost = 0
	for {
		cur := 0
		minCost := INF
		for i := 0; i < N; i++ {
			n := nodes[i]
			if !n.done && n.cost < minCost {
				cur = i
				minCost = n.cost
			}
		}
		if minCost == INF {
			break
		}
		nodes[cur].done = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+nodes[cur].cost
			if !nodes[to].done && cost < nodes[to].cost {
				nodes[to].cost = cost
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, nodes[i].cost)
	}
	wtr.Flush()
}

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

class TNode
{
	std::list<std::pair<TNode*, int> > FNexts;
	int  FDistance;
public:
	TNode()
	: FDistance(-1)
	{
	}
	
	int GetDistance()const {return FDistance;}
	
	void Push(TNode* New, int Weight)
	{
		FNexts.push_back(std::make_pair(New, Weight));
	}
	
	void Visit(int Distance)
	{
		if(FDistance >= 0 && Distance > FDistance) return;
		FDistance = Distance;
		for(std::list<std::pair<TNode*, int> >::iterator It = FNexts.begin(); It != FNexts.end(); ++It){
			It->first->Visit(Distance + It->second);
		}
	}
};

class TGraph
{
	std::vector<TNode*> FNodes;
public:
	TGraph(int Count)
	: FNodes(Count)
	{
		for(int i = 0; i < Count; ++i){
			FNodes[i] = new TNode();
		}
	}
	
	~TGraph()
	{
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			delete FNodes[i];
		}
	}
	
	void InputNode()
	{
		int Index;
		std::cin >> Index;
		int BranchCount;
		std::cin >> BranchCount;
		for(int i = 0; i < BranchCount; ++i){
			int Target, Weight;
			std::cin >> Target >> Weight;
			FNodes[Index]->Push(FNodes[Target], Weight);
		}
	}
	
	void BreathFirstSearch()
	{
		FNodes[0]->Visit(0);
	}
	
	int Distance(int Target)const
	{
		return FNodes[Target]->GetDistance();
	}
};

int main()
{
	int Count;
	std::cin >> Count;
	TGraph Graph(Count);
	for(int i = 0; i < Count; ++i){
		Graph.InputNode();
	}
	Graph.BreathFirstSearch();
	
	for(int i = 0; i < Count; ++i){
		std::cout << i << " " << Graph.Distance(i) << std::endl;
	}
	return 0;
}

C++: #include<iostream>
using namespace std;
static const int MAX=100;
static const int INFTY=(1<<21);
static const int white=01;
static const int gray=1;
static const int black=2;

int n,M[MAX][MAX];
void dijkstra(){
    int minv;
    int d[MAX],color[MAX];

    for(int i=0;i<n;i++){
	d[i]=INFTY;
	color[i]=white;
    }
    d[0]=0;
    color[0]=gray;
    while(1){
	minv=INFTY;
	int u=-1;
	for(int i=0;i<n;i++){
	    if(minv>d[i]&&color[i]!=black){
		u=i;
		minv=d[i];
	    }
	}
	if(u==-1)break;

	color[u]=black;
	for(int v=0;v<n;v++){
	    if(color[v]!=black&&M[u][v]!=INFTY){
		if(d[v]>d[u]+M[u][v]){
		    d[v]=d[u]+M[u][v];
		    color[v]=gray;
		}
	    }
	}
    }
    for(int i=0;i<n;i++){
	cout<<i<<" "<<(d[i]==INFTY?-1:d[i])<<endl;
    }
}
int main(){
    cin>>n;
    for(int i=0;i<n;i++){
	for(int j=0;j<n;j++){
	    M[i][j]=INFTY;
	}
    }

    int k,c,u,v;
    for(int i=0;i<n;i++){
	cin>>u>>k;
	for(int j=0;j<k;j++){
	    cin>>u>>c;
	    M[u][v]=c;
	}
    }
    dijkstra();
    return 0;
}

C++: #include<iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];
    
    for(int i = 0; i < n; i++){
        d[i] = INFTY;
        color[i] = WHITE;
    }
    
    d[0] = 0;
    color[0] = GRAY;
    while(1){
        minv = INFTY;
        int u = -1;
        for(int i = 0; i < n; i++){
            if( (minv > d[i]) && (color[i] != BLACK) ){
                u = i;
                minv = d[i];
            }
        }
        
        if(u == -1) break;
        color[u] = BLACK;
        for(int v = 0; v < n; v++){
            if(  (color[v] != BLACK) && (M[u][v] != INFTY) ){
                if(d[v] > (d[u] + M[u][v]) ){
                    d[v] = d[u] + M[u][v];
                    color[v] = GRAY;
                }
            }
        }
    }
    
    for(int i = 0; i < n; i++){
        cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
    }
}

int main(){
    cin >> n;
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            M[i][j] = INFTY;
        }
    }
    
    int k, c, u, v;
    for(int i = 0; i < n; i++){
        cin >> u >> k;
        for(int j = 0; j < k; j++){
            cin >> v >> c;
            M[u][v] = c;
        }
    }
    
    dijkstra();
    
    return 0;
}

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

#define INF (1 << 21)

int main() {
	int node_num;

	std::cin >> node_num;
	std::vector<std::vector<int> > node(node_num, std::vector<int>(node_num, -1));

	for (size_t i = 0; i < node.size(); i++) {
		int out, node_number;
		std::cin >> node_number >> out;
		for (int j = 0; j < out; j++) {
			int to, distance;
			std::cin >> to >> distance;
			node[node_number][to] = distance;
		}
	}

	std::vector<int> distance(node.size(), INF);
	distance[0] = 0;

	int node_number = 0;
	for (size_t i = 0; i < node.size(); i++) {
		int min = INF;
		for (size_t j = 0; j < node[i].size(); j++) {
			if (node[node_number][j] != -1 && node[node_number][j] + distance[node_number] < distance[j]) {
				distance[j] = node[node_number][j] + distance[node_number];
				if (min == INF) {
					min = j;
				}else if (distance[min] > distance[j]) {
					min = j;
				}
			}
		}
		node_number = min;
		if (node_number == INF) break;
	}

	for (size_t i = 0; i < distance.size(); i++) {
		std::cout << i << " " << distance[i] << std::endl;
	}
}