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

//def
#define debug(x) cout << #x << ": " << x << '\n'
#define out(x) cout << x << '\n'
#define repeat(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define revrepeat(i, a, b) for (int i = (int)(b)-1; i >= (int)(a); i--)
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define revrep(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define foreach(e, v) for (auto &e : v)
#define all(x) (x).begin(), (x).end()
#define CYES cout << "Yes" << endl
#define CNO cout << "No" << endl
#define SPC(x) cout << fixed << setprecision(x)
#define ZERO(a) memset(a, 0, sizeof(a))
#define MINUS(a) memset(a, 0xff, sizeof(a))

typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<vector<int>> vii;
typedef vector<ll> vl;
typedef vector<vector<ll>> vll;
typedef pair<int, int> P;
constexpr int MOD = 1e9 + 7;
constexpr int INF = __INT_MAX__;               // 2^31 - 1
constexpr long long INFLL = __LONG_LONG_MAX__; // 2^61 - 1
constexpr int MAX_N = 1e5 + 5;
constexpr double PI = acos(-1);

int pre[MAX_N];
long long d[MAX_N];
bool seen[MAX_N];
struct Edge {
    int to;
    long long cost;
};
// require: cost value is positive
// O(nlog|v|)
void dijkstra(int s, vector<vector<Edge>> &graph) {
    fill(pre, pre + MAX_N, -1);
    fill(seen, seen + MAX_N, false);
    fill(d, d + MAX_N, INF);

    auto comPair = [](const P one, const P two) {
        return one.second > two.second;
    };
    // que(v, distance)
    priority_queue<P, vector<P>, decltype(comPair)> que(comPair);
    que.emplace(0, 0);
    d[0] = 0;
    seen[0] = true;

    while (!que.empty()) {
        int u = que.top().first;
        que.pop();

        for (auto e : graph[u]) {
            int v = e.to;
            int c = e.cost;

            if (not seen[v] and d[v] > d[u] + c) {
                d[v] = d[u] + c;
                pre[v] = u;
                que.emplace(v, d[v]);
            }
        }
        seen[u] = true;
    }
};

int main() {
    int n;
    cin >> n;
    vector<vector<Edge>> graph(n);
    int k;
    rep(i, n) {
        cin >> k;
        cin >> k;
        rep(j, k) {
            Edge e;
            cin >> e.to >> e.cost;
            graph[i].push_back(e);
        }
    }
    dijkstra(0, graph);
    rep(i, n) {
        cout << i << ' ' << d[i] << endl;
    }
}

C++: 
#include<iostream>
#include<cstdio>
#include<set>
#include<queue>
#include<cstring>
#include<algorithm>
typedef long long ll;
#define inf 1000000000
using namespace std;


struct _node
{
	ll v,w;
	//:v(a),w(b)
	_node(ll a=0,ll b=0)
	{
		v=a;
		w=b;
	
	};
	bool operator <(const _node & other) const
	{
		return other.w<w;
	}
	
}node;

vector<_node> A[10500];
bool mark[10500];
ll dis[10500];

priority_queue<_node> Q;

void add(ll a,ll b,ll c)
{
	//cout<<a<<" "<<b<<" "<<c<<endl; 
	A[a].push_back(_node(b,c));
	//cout<<A[a][0].w<<endl;
	
}


void dlsj(ll n)
{
	//while(!Q.empty())Q.pop();
	ll v,v1;
	_node tmp;
	for(int i=0;i<n;i++)dis[i]=inf;

	dis[0]=0;
	Q.push(_node(0,0));
	
	while(!Q.empty())
	{
		tmp=Q.top();
		Q.pop();
		v=tmp.v;
		//cout<<v<<endl;
		//cout<<A[v].size()<<endl;
		if(mark[v])continue;
		mark[v]=1;
		for(int i=0;i<A[v].size();i++)
		{
			
			if(mark[A[v][i].v])continue;
			v1=A[v][i].v;
			//cout<<i<<" "; 
			//cout<<dis[2]<<" "<<dis[A[v][i].v]<<" "<<dis[v]+A[v][i].w<<endl;
			//cout<<A[v][i].v<<endl;
			if(dis[v1]>dis[v]+A[v][i].w)
			{
				
				dis[v1]=dis[v]+A[v][i].w;
				
				Q.push(_node(A[v][i].v,dis[v1]));
				
			}
			
			
			
			
		} 
		
		
	}
	
	
	
	
}




int main()
{
	ll n;
	scanf("%lld",&n);
	add(0,0,0);
	for(int i=1;i<=n;i++)
	{
		ll u,k,a,b;
		scanf("%lld%lld",&u,&k);
		while(k--)
		{
			scanf("%lld%lld",&a,&b);
			add(u,a,b);
		}
		
		
		
		
	} 
	dlsj(n);
	for(int i=0;i<n;i++)
	{
		//cout<<"e"<<endl;
		cout<<i<<" "<<dis[i]<<endl;
		
	}
	
}

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

using namespace std;
 
vector<int> dijkstra(int s, vector<vector<pair<int, int> > >& G) {
	const int INF = 1e9;
	const int N = G.size();
	vector<int> cost(N, INF);
	priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > pq;
	cost[s] = 0;
	pq.push(make_pair(0, s));
	while (!pq.empty()) {
		pair<int, int> p = pq.top(); pq.pop();
		int now = p.second;
		if (cost[now] < p.first) continue;
		for (auto next : G[now]) {
			int nv = next.first, nw = next.second;
			if (cost[nv] > cost[now] + nw) {
				cost[nv] = cost[now] + nw;
				pq.push(make_pair(cost[nv], nv));
			}
		}
	}
	return cost;
}

int main() {
	int n; cin >> n;
	vector<vector<pair<int, int> > > G(n);
	for (int i = 0; i < n; ++i) {
		int u, k; cin >> u >> k;
		while (k--) {
			int v, c; cin >> v >> c;
			G[u].push_back(make_pair(v, c));
		}
	}
	vector<int> ans(dijkstra(0, G));
	for (int i = 0; i < n; ++i)
		cout << i << " " << ans[i] << endl;

	return 0;
}