Go: package main

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

type Node struct {
	Id int
	Dis int
}

type PriorityQueue []*Node

func (pq PriorityQueue) Len() int { return len(pq) }

func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].Dis < pq[j].Dis
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}

func (pq *PriorityQueue) Push(x interface{}) {
	*pq = append(*pq, x.(*Node))
}

func (pq *PriorityQueue) Pop() interface{} {
	n := len(*pq)
	pop := (*pq)[n-1]
	*pq = (*pq)[0:n-1]
	return pop
}

func main() {
	var n int
	fmt.Scan(&n)

	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	g := make([][]int, n)
	c := make([][]int, n)
	pq := make(PriorityQueue, 0, n)
	d := make([]int, n)
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		g[u] = make([]int, k)
		c[u] = make([]int, k)
		for j := 0; j < k; j++ {
			sc.Scan()
			g[u][j], _ = strconv.Atoi(sc.Text())
			sc.Scan()
			c[u][j], _ = strconv.Atoi(sc.Text())
		}

		if u == 0 {
			d[u] = 0
		} else {
			d[u] = 1 << 30
		}
		pq.Push(&Node{u, d[u]})
	}
	heap.Init(&pq)

	for pq.Len() > 0 {
		node := heap.Pop(&pq).(*Node)
		for i := 0; i < len(g[node.Id]); i++ {
			nextId := g[node.Id][i]
			nextDis := node.Dis + c[node.Id][i]
			if nextDis < d[nextId] {
				d[nextId] = nextDis
				heap.Push(&pq, &Node{nextId, nextDis})
			}
		}
	}

	wr := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		wr.WriteString(strconv.Itoa(i))
		wr.WriteString(" ")
		wr.WriteString(strconv.Itoa(d[i]))
		wr.WriteString("\n")
	}
	wr.Flush()
}

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

#define rep(n) for(int i=0;i<n;i++)
#define repp(j, n) for(int j=0;j<n;j++)
#define reppp(i, m, n) for(int i=m;i<n;i++)
#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef pair<int, int> Pii;
struct edge{int from, to; ll cost;};

const ll MOD = 1000000007;
const double EPS = 1e-9;

map<ll, ll> d;
priority_queue< Pll, vector<Pll>, greater<Pll> > que;
map<ll, vector<Pll> > edges;

void dijkstra(ll start){
    d[start] = 0;
    que.push(Pll(0, start));

    while(!que.empty()){
        Pll v = que.top(); que.pop();
        if(d.find(v.second) != d.end() && d[v.second] < v.first) continue;
        rep(edges[v.second].size()){
            Pll e = edges[v.second][i];
            if(d.find(e.first) == d.end() || d[e.first] > d[v.second] + e.second){
                d[e.first] = d[v.second] + e.second;
                que.push(Pll(d[e.first], e.first));
            }
        }
    }
}

int main(){
    std::ios::sync_with_stdio(0); cin.tie(0);
    int n;
    cin >> n;

    rep(n){
        ll u, k, c, v;
        cin >> u >> k;
        repp(j, k){
            cin >> v >> c;
            edges[u].emplace_back(v, c);
        }
    }

    dijkstra(0);
    repp(u, n){
        cout << u << " " << d[u] << endl;
    }

}

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

#define REP(i, n) for(int i=0;i<(int)(n);i++)
#define ALL(x) (x).begin(),(x).end()
const int INF = 1e9;

using namespace std;
int n;
int res = 0;
struct node {
    int id;
    int dist;
    bool searched;
};

node v[10000];
vector<pair<int, int>> edge[10000];

int main() {
    cin >> n;
    REP(i, n) {
        int u, k;
        cin >> u >> k;
        v[u].id = u;
        v[u].dist = INF;
        v[u].searched = false;
        REP(j, k){
            int to, cost;
            cin >> to >> cost;
            edge[i].push_back(make_pair(to, cost));
        }
    }
    v[0].dist = 0;
    int prev = 0;
    REP(i, n){
        int minimum = INF;
        REP(j, n){
            if(!v[j].searched && minimum >= v[j].dist){
                prev = j;
                minimum = v[j].dist;
            }
        }
        while(!edge[prev].empty()){
            int s = edge[prev].size() - 1;
            int j = edge[prev][s].first;
            v[j].dist = min(v[j].dist, v[prev].dist + edge[prev][s].second);
            edge[prev].pop_back();
        }
        v[prev].searched = true;
    }
    REP(i, n) cout << i << " " << v[i].dist << endl;
    return 0;
}

C++: #include <stdio.h>
#include <iostream>
#include <queue>
#include <list>
using namespace std;

class Node
{
private:
	list<int> next_node_list;
	list<int> next_weight_list;
public:
	Node();
	void AddNextNode(int id, int weight);
	void SetWeight(int weight);
	void DistributeWeight();
	int weight_from_0;
	bool check;
};

Node::Node()
{
	weight_from_0 = -1;
	check = false;
}

Node *Node_list;

struct GreatNode
{
	bool operator()(const Node *n1, const Node *n2) const;
};
bool GreatNode::operator()(const Node *n1, const Node *n2) const
{
	return n1->weight_from_0 > n2->weight_from_0;
}
priority_queue<Node*, vector<Node*>, GreatNode > Q;

void Node::AddNextNode(int id, int weight)
{
	next_node_list.push_back(id);
	next_weight_list.push_back(weight);
}

void Node::SetWeight(int weight)
{
	if (weight_from_0 == -1 || weight < weight_from_0) {
		weight_from_0 = weight;
	}
}

void Node::DistributeWeight()
{
	check = true;
	list<int>::iterator itr2 = next_weight_list.begin();
	for(list<int>::iterator itr = next_node_list.begin(); itr != next_node_list.end(); itr++){	
		if (Node_list[*itr].check == false) {
			Node_list[*itr].SetWeight(weight_from_0 + *itr2);
			Q.push(&Node_list[*itr]);
		}
		itr2++;
	}
	next_node_list.clear();
	next_weight_list.clear();
}

int main(void)
{
	//input
	int n;
	cin >> n;
	Node_list = new Node[n]();
	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			int v, c;
			cin >> v >> c;
			Node_list[u].AddNextNode(v, c);
		}
	}

	//weight from 0 ?
	Node_list[0].weight_from_0 = 0;
	Node_list[0].DistributeWeight();
	while (!Q.empty()) {
		Node *node = Q.top();
		Q.pop();
		node->DistributeWeight();
	}

	//output
	for (int i = 0; i < n; i++) {
		cout << i << " " << Node_list[i].weight_from_0 << endl;
	}
	
	return 0;
}

C++: #include<iostream>
#include<vector>
#include<queue>
#define MAX 10000
#define INF (1<<21)
using namespace std;

int n;
vector<pair<int,int> > E[MAX];
int d[MAX];

void dijkstra(int s){
    priority_queue<pair<int,int> > PQ;
    int visited[MAX];
    for(int i=0;i<n;i++){
        visited[i]=false;
    }
    d[s]=0;
    PQ.push(make_pair(d[s],s));
    while(!PQ.empty()){
        pair<int,int> f=PQ.top();
        PQ.pop();
        int u=f.second;
        visited[u]=true;

        if(d[u]<f.first*(-1)) continue;

        for(int j=0;j<E[u].size();j++){
            int v=E[u][j].first;   //之前这里写错了
            if(visited[v]==true) continue;
            if(d[v]>d[u]+E[u][j].second){
                d[v]=d[u]+E[u][j].second;
                PQ.push(make_pair(d[v]*(-1), v));
            }
        }

    }


}

void init(){
    int k,b,e,val;
    cin>>n;
    for(int i=0;i<n;i++){
        d[i]=INF;
        cin>>b>>k;
        for(int j=0;j<k;j++){
            cin>>e>>val;
            E[b].push_back(make_pair(e,val));
        }
    }
}

int main(){
    init();

    /*for(int i=0;i<n;i++){
        for(int j=0;j<E[i].size();j++){
            cout<<E[i][j].first<<":"<<E[i][j].second<<' ';
        }
        cout<<endl;
    }*/

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

    return 0;
}