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
	heap.Init(&pq)

	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++: #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<algorithm>
#include<queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int> > adj[MAX];  // 重み付き有向グラフの隣接リスト表現

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

  d[0] = 0;
  PQ.push(make_pair(0, 0));
  color[0] = GRAY;

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

    color[u] = BLACK;

    // 最小値を取り出し、それが最短でなければ無視
    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] == BLACK ) continue;
      if ( d[v] > d[u] + adj[u][j].second ) {
        d[v] = d[u] + adj[u][j].second;
        // priority_queue はデフォルトで大きい値を優先するため -1 を掛ける
        PQ.push(make_pair(d[v] * (-1), v));
        color[v] = GRAY;
      }
    }
  }

  for ( int i = 0; i < n; i++ )
    cout << i << " " << ( d[i] == INFTY ? -1 : d[i] ) << endl;
}

int main() {
  int k, u, 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();

  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

typedef pair<int, int> node;
typedef vector<node> Adj_list;
typedef vector<Adj_list> Adj_lists;

class less_cost{
public:
  bool operator()(const node lhs, const node rhs) const{
    return lhs.second > rhs.second;
  }
};

int main(){

  int n;
  scanf("%d", &n);

  Adj_lists adj_lists(n);

  // read weigts
  for(int i=0; i<n; i++){
    int u, k;
    scanf("%d %d", &u, &k);
    for(int j=0; j<k; j++){
      int v,c;
      scanf("%d %d", &v, &c);
      adj_lists.at(u).push_back(node(v, c));
    }
  }

  // initialize cost
  vector<int> d(n, INT_MAX);
  d.at(0) = 0;
  priority_queue<node, vector<node>, less_cost> pq;
  pq.push(node(0, d.at(0)));
  vector<bool> is_belong_to_sssp(n, false);

  //dijkstra's algorithm
  while(!pq.empty()){
    // extract node u in V-S that has minimum cost
    const node u = pq.top();
    pq.pop();

    // if u's cost is larger than d[u],
    // than ignore this one
    if(u.second > d.at(u.first)) continue;


    is_belong_to_sssp.at(u.first) = true;

    // update node in V-S and adjacent to u
    for(const node& v : adj_lists.at(u.first)){
      if(!is_belong_to_sssp.at(v.first) && d.at(u.first) + v.second < d.at(v.first)){
        d.at(v.first) = d.at(u.first) + v.second;
        pq.push(node(v.first, d.at(v.first)));
      }
    }
  }

  // output
  for(int i=0; i<n; i++){
    printf("%d %d\n", i, d.at(i));
  }

  return 0;
}

C++: #include<iostream>
using namespace std;
#include<queue>
#include<vector>
#include<string>
#include<string.h>
#include<algorithm>
bool b[2003];

#define REP(i, a) for(int i=0;i<a;i++)
	int N=(1<<20);
int main()
{
	pair<int,int> f;
	vector < pair<int,int> > A[10001];
	priority_queue < pair < int,int > > PQ;
	int min,b,a,k,m,n ,e,p[101],d[101],u,v; //u ?????????v????????¨
	bool color[10001];

	cin>>n;
	REP(i, n) {
		cin>>u>>k;
		REP(i, k) {
			cin>>a>>b;
			if(b==-1) b=N;
			A[u].push_back(make_pair(a,b));
		}
		color[i]=0;
		d[i]=N;
	}
	a=0;
	d[0]=0;
	PQ.push(make_pair(0,0));
	while(!PQ.empty()){
		f=PQ.top();
		PQ.pop();
		u=f.second;
		color[u]=1;
		REP(i,A[u].size()){
			v=A[u][i].first;
			if(color[v]==1){
			continue;
			}
				if(d[v]>A[u][i].second+d[u]){
					d[v]=A[u][i].second+d[u];
					PQ.push(make_pair(d[v]*-1,v));
				}
		}
	}
	REP(i,n){
		cout<<i<<" "<<(d[i] == N ? -1 : d[i])<<endl;
	
	}
	return 0;
}