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 <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define MAX 10000
#define INF (1<<30)

using namespace std;
enum state{
  BLACK,
  WHITE
};

int main(){
  vector<pair<int,int>> a[MAX];
  int n; cin>>n;
  int d[MAX];
  state s[MAX];

  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;
      a[u].push_back(make_pair(v,c));
    }
  }

  for(int i=0;i<n;i++){
    s[i]=WHITE;
    d[i]=INF;
  }
  d[0]=0;

  priority_queue<pair<int,int>> q;
  q.push(make_pair(0,0));

  while(!q.empty()){
    pair<int,int> p;
    p = q.top(); q.pop();
    if(s[p.second]==BLACK) continue;
    d[p.second]=p.first*-1;
    s[p.second]=BLACK;
    
    for(auto it = a[p.second].begin(); it!=a[p.second].end(); it++){
      int i = it->first;
      int cost = it->second;
      if(s[i]==WHITE && d[i] > d[p.second] + cost ){
        d[i]=d[p.second]+cost;
        q.push(make_pair(d[i]*-1,i));
      }
    }
  }
  
  for(int i=0;i<n;i++){
    printf("%d %d\n",i,d[i]);
  }


}

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

#define MAX_NODE 10000
#define INF 1000000000

using namespace std;

struct Edge {int to, w;};
typedef pair<int, int> PII;

vector<Edge> adj[MAX_NODE];
int d[MAX_NODE];

void dijkstra(int n, int start) {
	priority_queue<PII, vector<PII>, greater<PII>> que;
	fill(d, d + n, INF);

	d[start] = 0;
	que.emplace(0, start);
	while (!que.empty()) {
		PII p = que.top();
		que.pop();
		int from = p.second;

		if (d[from] < p.first)
			continue;

		for (auto& e : adj[from])
			if (d[from] + e.w < d[e.to]) {
				d[e.to] = d[from] + e.w;
				que.emplace(d[e.to], e.to);
			}
	}
}

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

	int n;

	cin >> n;

	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		while (k--) {
			int v, c;
			cin >> v >> c;
			adj[u].push_back({v, c});
		}
	}

	dijkstra(n, 0);

	for (int i = 0; i < n; i++)
		cout << i << " " << d[i] << endl;

	return 0;
}