Go: package main

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

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

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

// we want the ascending-priority-queue.
// So we use less than here.
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}

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

func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 //for safety
	*pq = old[0 : n-1]
	return item
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist [][]int, n int) []int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range dist[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return shortests
}

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

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(dist, n)
	for i, d := range shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: ///
// File:  alds1_12_c.cpp
// Author: ymiyamoto
//
// Created on Wed Oct 18 22:36:29 2017
//

#include <cstdint>
#include <iostream>
#include <queue>
#include <vector>

using namespace std;

#define SIZE 10000

struct route_t {
  uint32_t node;
  int64_t weight;

  bool operator<(const route_t &r) const
  {
    return weight > r.weight;
  }
};

static vector<route_t> graph[SIZE];
static int64_t costs[SIZE];
static bool visited[SIZE];
static priority_queue<route_t> q;

static void dikstra()
{
  q.push({0, 0});
  costs[0] = 0;

  while (!q.empty()) {
    route_t r = q.top();
    q.pop();

    if (!visited[r.node]) {
      visited[r.node] = true;
      for (uint32_t i = 0; i < graph[r.node].size(); i++) {
        int64_t cost = costs[r.node];
        uint32_t node = graph[r.node][i].node;
        if (cost != -1) {
          if (costs[r.node] + cost < costs[node]) {
            costs[node] = costs[r.node] + cost;
            q.push({node, costs[node]});
          }
        }
      }
    }
  }
}

int32_t main()
{
  uint32_t n;
  cin >> n;

  for (uint32_t i = 0; i < n; i++) {
    costs[i] = INT32_MAX;
  }

  for (uint32_t i = 0; i < n; i++) {
    uint32_t id, k;
    cin >> id >> k;
    for (uint32_t j = 0; j < k; j++) {
      route_t r;
      cin >> r.node >> r.weight;
      graph[id].push_back(r);
    }
  }

  dikstra();

  for (uint32_t i = 0; i < n; i++) {
    cout << i << " " << costs[i] << endl;
  }

  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

struct edge{int to,cost;};
using Graph=vector<vector<edge>>;
using pint=pair<int,int>;
const int INF=1e9;

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    int N; cin>>N;
    Graph 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({v,c});
        }
    }

    vector<int> dist(N,INF),finished(N,false);
    priority_queue<pint,vector<pint>,greater<pint>> Q;
    dist[0]=0;
    Q.push({0,0});
    while(!Q.empty()){
        int v=Q.top().second; Q.pop();
        if(finished[v]) continue;
        finished[v]=true;
        for(edge e:G[v]) if(chmin(dist[e.to],dist[v]+e.cost)){
            Q.push({dist[e.to],e.to});
        }
    }
    for(int i=0;i<N;i++){
        cout<<i<<' '<<dist[i]<<endl;
    }
    return 0;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <iostream>
#include <vector>
#include <queue>
#include <functional>
using namespace std;
const int INF = 2000000000;
const int num = 10000;
int n, k, u, v, w;
int c[num];
int d[num];
vector <pair<int, int> > ve[num];
int main() {
	priority_queue <pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > q;
	fill(d, d + num, INF);
	d[0] = 0;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v >> w;
			ve[u].push_back(make_pair(v, w));
		}
	}
	fill(c, c + num, 0);
	q.push(make_pair(0, 0));
	while (!q.empty()) {
		int f = q.top().first;
		int s = q.top().second;
		q.pop();
		c[s] = 1;
		if (d[s] < f) continue;
		for (int i = 0; i < ve[s].size(); i++) {
			int fi = ve[s][i].first;
			int se = ve[s][i].second;
			if (c[fi]) continue;
			if (d[fi] > d[s] + se) {
				d[fi] = d[s] + se;
				q.push(make_pair(d[fi], fi));
			}
		}
	}
	for (int i = 0; i < n; i++) cout << i << " " << d[i] << endl;
	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
static const int MAX = 10000; 
int n;
vector<pair<int, int>> adj[MAX];
void dij(){
	priority_queue<pair<int,int>> que;
	int d[MAX],color[MAX];
	for(int i = 0;i < n;i++){
		d[i] = INT_MAX;
		color[i] = 0;
	}
	d[0] = 0;
	que.push(make_pair(0,0));
	color[0] = 1;
	while(!que.empty()){
		pair<int,int> f = que.top();
		que.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;
				que.push(make_pair(d[v]*(-1),v));
				color[v] = 1;
			}
		}
	}
	for(int i = 0;i < n;i++){
		cout << i << " " << (d[i] == INT_MAX ? -1 : d[i]) << endl;
	}
}
int main(){
	cin >> n;
	int k, c, u,v;
	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));
		}
	}
	dij();
}