Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

const NIL = -1

type Node struct {
	id     int
	weight int
}

func init() {
	sc.Split(bufio.ScanWords)
}

type NodeHeap []Node

func (h NodeHeap) Len() int           { return len(h) }
func (h NodeHeap) Less(i, j int) bool { return h[i].weight < h[j].weight }
func (h NodeHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

func (h *NodeHeap) Push(x interface{}) {
	*h = append(*h, x.(Node))
}

func (h *NodeHeap) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}

var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func main() {
	n := scanInt()

	route := make([][]Node, n)
	weight := make([]int, n)
	for i := 0; i < n; i++ {
		weight[i] = NIL
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		route[i] = make([]Node, k)
		for j := 0; j < k; j++ {
			route[u][j] = Node{id: scanInt(), weight: scanInt()}
		}
	}

	start := Node{id: 0, weight: 0}
	h := &NodeHeap{start}
	heap.Init(h)

	for h.Len() > 0 {
		node := heap.Pop(h).(Node)
		if weight[node.id] != NIL {
			continue
		}
		weight[node.id] = node.weight

		for _, nextNode := range route[node.id] {
			if weight[nextNode.id] != NIL {
				continue
			}
			nextNode.weight += node.weight
			heap.Push(h, nextNode)
		}
	}

	for i, w := range weight {
		fmt.Println(i, w)
	}
}

C++: 
#include<stdio.h>
#include<algorithm>
#include<queue>

using namespace std;

#define MAX 10000
#define INFINITY 300000

int n;
int color[MAX], d[MAX];

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

enum Color {
    WHITE,
    GRAY,
    BLACK
};

void dijkstra() {
    priority_queue<pair<int, int> >PQ;
    for (int i = 0; i < n; ++i) {
        color[i] = WHITE;
        d[i] = INFINITY;
    }
    d[0] = 0;
    PQ.push(make_pair(0,0));

    while (!PQ.empty()) {
        pair<int, int> p = PQ.top();
        PQ.pop();
        int target = p.second;

        color[target] = BLACK;
        if (d[target] < p.first * -1) continue;

        for (int j = 0; j < adj[target].size(); ++j) {
            int v = adj[target][j].first;
            if (color[v] != BLACK) {
                if(adj[target][j].second + d[target] < d[v]) {
                    d[v] = d[target] + adj[target][j].second;
                    color[v] = GRAY;
                    PQ.push(make_pair(d[v] * -1, v));
                }
            }
        }
    }

    for (int i = 0; i < n; ++i) {
        printf("%d %d\n", i, d[i]);
    }
}

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

C++: #include <iostream>
// #include <vector> 
#include <algorithm>
#include <queue>
#include <cstdio> 
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<20);
int d[MAX],color[MAX];
int n;
vector<pair<int, int> > adj[MAX];

void dijkstra()
{
    priority_queue<pair<int, int> > PQ;
    for (int i = 0; i < n; i++)
    {
        d[i] = INFTY;
        color[i] = 0;
    } 
    d[0] = 0;
    PQ.push(make_pair(0,0));
    color[0] = 1;
    while (!PQ.empty())
    { 
        pair<int, int> f = PQ.top(); PQ.pop();
        int u = f.second;
        color[u] = 2;
        
        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] == 2) 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] = 1;
            } 
        } 
    } 

    return;
}


int main()
{
    //freopen("in3.txt","r",stdin);
    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;
            adj[u].push_back(make_pair(v,c));
        } 
    } 
    dijkstra();
    for (int i = 0; i < n; i++)
    {
        cout<<i<<" "<<d[i]<<endl; 
    } 
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<vector>
#include<utility>
#include<limits>
using namespace std;
typedef pair<int, int> Edge;
int main()
{
	int n; cin >> n;
	vector< vector< Edge > > lists;

	for (int i = 0; i < n; i++)
	{
		vector<Edge> list;
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; j++)
		{
			Edge edge;
			cin >> edge.second >> edge.first;
			list.push_back(edge);
		}
		lists.push_back(list);
	}

	vector<int> costs(n, INT32_MAX);
	costs[0] = 0;
	priority_queue<Edge> queue;
	for (Edge edge : lists[0])
		queue.push(edge);

	while (!queue.empty())
	{
		Edge edge = queue.top(); queue.pop();
		int dest = edge.second;
		int cost = edge.first;
		if (costs[dest] < cost)continue;
		int new_cost = costs[edge.second] = edge.first;

		for (Edge next : lists[dest])
		{
			next.first += new_cost;
			if(costs[next.second]== INT32_MAX)
				queue.push(next);
		}
	}
	for (int i = 0; i < n; i++)
		cout << i << " " << costs[i] << endl;

	char c;
	cin >> c;

	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#define INF 1<<21
#include<vector>
static const int N = 10000;
using namespace std;
vector<pair<int,int> > A[N];
int n;
void dajkstra(void){
    priority_queue<pair<int, int> > PQ;
    int d[N],color[N];
    for(int i=0;i<n;i++){
        d[i] = INF;
        color[i] = 0;
    }
    d[0] = 0;
    PQ.push(make_pair(0,0));
    while(!PQ.empty()){
        pair<int, int> f = PQ.top(); PQ.pop();
        int u = f.second;
        color[u] = 1;
        if(d[u]<f.first*(-1)){
                continue;
        }
        for(int j=0;j<A[u].size();j++){
            int v = A[u][j].first;
            if(color[v]==1){
                continue;
            }
            if(d[u] + A[u][v].second < d[v]){
                d[v] = d[u] + A[u][v].second;
                PQ.push(make_pair(d[v]*(-1),v));
            }
        }
    }
    for(int i=0;i<n;i++){
        cout << i << ' ' << d[i] << endl;
    }
}
int main(void){
    int u,v,adj,key;
    cin >> n;
    for(int i=0;i<n;i++){
        cin >> u >> adj;
        for(int j=0;j<adj;j++){
            cin >> v >> key;
            A[u].push_back(make_pair(v,key));
        }
    }
    dajkstra();
    return 0;
}