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 <vector>
#include <map>
#include <queue>
#include <algorithm>
#define INF 1<<30
using namespace std;
int main() {
	cin.tie(0);ios::sync_with_stdio(false);
	int V; cin >> V;
	vector<vector<pair<int, int>>> g(V);
	vector<int> dp(V);
	queue<int> q;

	//input
	for (int i = 0; i < V; i++) {
		int u, k; cin >> u >> k;
		for (int j = 0; j < k; j++) {
			int c, v;
			cin >> c >> v;
			g[u].push_back(make_pair(c, v));
		}
	}

	//initialize
	fill(dp.begin(), dp.end(), INF);
	dp[0] = 0;
	q.push(0);

	//Dijkstra
	while (!q.empty()) {
		int k = q.front(); q.pop();
		for (int i = 0; i < g[k].size();i++) {
			int next = g[k][i].first;
			int w = g[k][i].second;
			if (dp[k] + w < dp[next]) {
				dp[next] = dp[k] + w;
				q.push(next);
			}
		}
	}

	//output
	for (int i = 0; i < V;i++) {
		cout << i << " " << dp[i] << endl;
	}
}

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 <bits/stdc++.h>
using namespace std;

#define INF (INT64_MAX/2)
typedef pair<long long, int> P;

int main()
{
	int n;
	cin >> n;
	vector<vector<P>> g( n );
	for( int i = 0; i < n; i++ ) {
		int u, k;
		cin >> u >> k;
		g[u].resize( k );
		for( int j = 0; j < k; j++ ) {
			int v, c;
			cin >> v >> c;
			g[u][j] = P( c, v );
		}
	}

	vector<long long> d( n, INF );
	d[0] = 0;
	priority_queue<P, vector<P>, greater<P>> que;
	que.push( P( 0, 0 ) );
	while( !que.empty() ) {
		P p = que.top();
		que.pop();
		int c = p.first;
		int u = p.second;
		for( P e : g[u] ) {
			int cost = e.first;
			int v = e.second;
			if( d[v] <= d[u] + cost ) continue;
			d[v] = d[u] + cost;
			que.push( e );
		}
	}

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

C++: //Single Source Shortest Path II
#include <iostream>
#include <vector>
#include <climits>

using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int BLACK = 1;
int n, colors[N], d[N];
vector<pair<int, int> > G[N];

void dijkstra() {
    int u, mind;
    for(int i = 0; i < N; i++) {
        colors[i] = WHITE;
        d[i] = INT_MAX;
    }
    d[0] = 0;
    while(1) {
        u = -1;
        mind = INT_MAX;
        for(int i = 0; i < n; i++) {
            if(colors[i] == WHITE && d[i] < mind) {
                u = i;
                mind = d[i];
            }
        }
        if(u == -1) break;
        colors[u] = BLACK;
        for(int i = 0; i < G[u].size(); i++) {
            d[G[u][i].first] = min(d[G[u][i].first], mind + G[u][i].second);
        }
    }
}

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

    dijkstra();

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