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 <queue>	
#include <utility>	
#include <list>		
#define N 10000	
#define INF (1<<31-1);
using namespace std;

typedef pair<int,int> pii;	
vector<pii> adj[N];	
bool color[N];	
int dist[N];	
int n;	
priority_queue<pii> pq; 

int dijkstra(int k){	
	for(int i=0;i<n;i++){
		color[i]=false; 
		dist[i]=INF;	
	}
	color[k]=true; 
	dist[k]=0;	
	for(int i=0;i<adj[k].size();i++){
		pq.push(adj[k][i]); 
	}
	while(!pq.empty()){	
		pii temp=pq.top();pq.pop();	
		temp.first=-temp.first;	
		if(color[temp.second])continue;	
		color[temp.second]=true; 
		dist[temp.second]=temp.first;	
		for(int i=0;i<adj[temp.second].size();i++){
			if(!color[adj[temp.second][i].second])pq.push(make_pair(-dist[temp.second]+adj[temp.second][i].first,adj[temp.second][i].second));
		}
	}

	for(int i=0;i<n;i++) cout<<i<<" "<<dist[i]<<endl;
	return 0;
}
int main(void){
	int v,c;	
	int u,k;	
	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(-c,v));	
		}
	}
	dijkstra(0);	
	return 0;
}

C++: # include "bits/stdc++.h"
using namespace std;
using LL = long long;
using ULL = unsigned long long;
const double PI = acos(-1);
template<class T>constexpr T INF() { return ::std::numeric_limits<T>::max(); }
template<class T>constexpr T HINF() { return INF<T>() / 2; }
template <typename T_char>T_char TL(T_char cX) { return tolower(cX); };
template <typename T_char>T_char TU(T_char cX) { return toupper(cX); };
typedef pair<LL, LL> pii;
const int vy[] = { -1, -1, -1, 0, 1, 1, 1, 0 }, vx[] = { -1, 0, 1, 1, 1, 0, -1, -1 };
const int dx[4] = { 0,1,0,-1 }, dy[4] = { 1,0,-1,0 };
int popcnt(unsigned long long n) { int cnt = 0; for (int i = 0; i < 64; i++)if ((n >> i) & 1)cnt++; return cnt; }
int d_sum(LL n) { int ret = 0; while (n > 0) { ret += n % 10; n /= 10; }return ret; }
int d_cnt(LL n) { int ret = 0; while (n > 0) { ret++; n /= 10; }return ret; }
LL gcd(LL a, LL b) { if (b == 0)return a; return gcd(b, a%b); };
LL lcm(LL a, LL b) { LL g = gcd(a, b); return a / g*b; };
# define ALL(qpqpq)           (qpqpq).begin(),(qpqpq).end()
# define UNIQUE(wpwpw)        sort(ALL((wpwpw)));(wpwpw).erase(unique(ALL((wpwpw))),(wpwpw).end())
# define LOWER(epepe)         transform(ALL((epepe)),(epepe).begin(),TL<char>)
# define UPPER(rprpr)         transform(ALL((rprpr)),(rprpr).begin(),TU<char>)
# define FOR(i,tptpt,ypypy)   for(LL i=(tptpt);i<(ypypy);i++)
# define REP(i,upupu)         FOR(i,0,upupu)
# define INIT                 std::ios::sync_with_stdio(false);std::cin.tie(0)
# pragma warning(disable:4996)

int V, E;
struct edge { LL to, cost; };
int start;
LL d[100100]; //距離
vector<edge> vec[1010];

void dijkstra() {
	for (int i = 0; i < 100100; i++)d[i] = HINF<LL>();
	priority_queue<pii, std::vector<pii>, std::greater<pii>> pq;
	d[start] = 0;
	pq.push(make_pair(d[start], start));//cost,to
	while (!pq.empty()) {
		pii p = pq.top();
		pq.pop();
		int i = p.second;
		if (d[i] < p.first)continue;
		for (int k = 0; k < vec[i].size(); k++) {
			edge e = vec[i][k];
			if (d[e.to] <= d[i] + e.cost)continue;
			d[e.to] = d[i] + e.cost;
			pq.push(make_pair(d[e.to], e.to));
		}
	}
}

int main() {
	cin >> V;
	REP(i, V) {
		int u;
		cin >> u;
		int num;
		cin >> num;
		REP(j, num) {
			int v, c;
			cin >> v >> c;
			vec[u].emplace_back(edge{ v,c });
		}
	}
	dijkstra();
	REP(i, V) {
		cout << i << " " << d[i] << endl;
	}
}

C++: 
#include<bits/stdc++.h>

using namespace std;

const int maxn=1e4+5;
const int inf=(1<<20);
const int white=0;
const int gray=1;
const int black=2;

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

void dijkstra()
{
    priority_queue<pair<int,int> >q;
    int book[maxn],d[maxn];
    for(int i=0;i<n;i++){
        d[i]=inf;
        book[i]=0;
    }
    d[0]=0;
    q.push(make_pair(0,0));
    while(!q.empty()){
        pair<int,int>f=q.top();
        q.pop();
        int u=f.second;
        book[u]=1;
        if(d[u]<f.first*(-1)){
            continue;
        }
        for(int j=0;j<adj[u].size();j++){
            int v=adj[u][j].first;
            if(book[v]==1){
                continue;
            }
            if(d[v]>d[u]+adj[u][j].second){
                d[v]=d[u]+adj[u][j].second;
                q.push(make_pair(d[v]*(-1),v));
            }
        }
    }
    for(int i=0;i<n;i++){
        cout<<i<<" "<<(d[i]==inf?-1:d[i])<<endl;
    }
}

int main()
{
    scanf("%d",&n);
    int u,k,v,c;
    for(int i=0;i<n;i++){
        cin>>u>>k;
        for(int i=0;i<k;i++){
            cin>>v>>c;
            adj[u].push_back(make_pair(v,c));
        }
    }
    dijkstra();
    return 0;
}