Go: package main

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

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
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 = i
	pq[j].index = j
}
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
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

C++: #include <iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];

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

    d[0] = 0;
    color[0] = GRAY;

    while(1){
        minv = INFTY;
        int u=-1;
        for(int i=0;i<n;i++){
            if(minv > d[i] && color[i] != BLACK){
                u = i;
                minv = d[i];
            }
        }
        if(u==-1) break;
        color[u] = BLACK;
        for(int v=0;v<n;v++){
            if(color[v] != BLACK && M[u][v] != INFTY){
                if(d[v]>d[u]+M[u][v]){
                    d[v] = d[u] + M[u][v];
                    color[v]= GRAY;
                }
            }
        }
    }

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

int main(){
    cin >> n;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++) M[i][j] = INFTY;
    }

    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;
            M[u][v] = c;
        }
    }

    dijkstra();

    return 0;

}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <queue>
#include <functional>

#define INPUT_FROM_FILE (0) 
#if INPUT_FROM_FILE
#include <fstream>
#endif

typedef std::pair<int, int> P;

class Edge{
public:
	int to;
	int cost;

	Edge(){
		return;
	}
	~Edge(){
		return;
	}
};

int main(int argc, char **argv){
	std::vector<std::vector<Edge> >  G;
	std::vector<long> min_cost;
	std::priority_queue<P, std::vector<P>, std::greater<P> > que;

	int n, u, k, v, c;

#if INPUT_FROM_FILE
	std::ifstream ifs("test.txt");
	//FILE *fp = fopen("test.txt", "r");
#endif

	
#if INPUT_FROM_FILE
	ifs >> n;
#else
	std::cin >> n;
#endif
	G.resize(n);
	min_cost.resize(n, 1000000000) ;

	for(int i = 0; i < n; i++){
#if INPUT_FROM_FILE
		ifs >> u >> k;
#else
		std::cin >> u >> k;
#endif
		for(int j = 0; j < k; j++){
#if INPUT_FROM_FILE
			ifs >> v >> c;
#else
			std::cin >> v >> c;
#endif
			Edge e;
			e.to = v;
			e.cost = c;

			G[u].push_back(e);

		}
	}

	min_cost[0] = 0;
	que.push(P(0, 0));

	while(!que.empty()){
		P p = que.top(); que.pop();
		int v = p.second;

		if(min_cost[v] < p.first){ 
			continue;
		}

		for(int i = 0; i < G[v].size(); i++){
			Edge e = G[v][i];
			if(min_cost[e.to] > min_cost[v] + e.cost){
				min_cost[e.to] = min_cost[v] + e.cost;
				que.push(P(min_cost[e.to], e.to));
			}
		}
	}

	for(int i = 0; i < n; i++){
		std::cout << i << " " << min_cost[i] << std::endl;
	}
	return 0;
}

C++: #include <iostream>
#include <vector>
#include <limits>

using namespace std;
using MatrixGraph = vector<vector<int>>;

const int infinity = numeric_limits<int>::max();
const int no_label = -1;

vector<int> calc_shortest_path(MatrixGraph matrix_graph, int started_label) {
  vector<int> min_costs(matrix_graph.size(), infinity);
  vector<bool> is_visits(matrix_graph.size(), false);

  min_costs[started_label] = 0;

  while(true) {
    int min_cost_adjacency_label = no_label;
    int min_cost_adjacency_weight = infinity;
    for(int i = 0; i < matrix_graph.size(); i++) {
      if(is_visits[i]) {
        continue;
      }

      if(min_costs[i] < min_cost_adjacency_weight) {
        min_cost_adjacency_label = i;
        min_cost_adjacency_weight = min_costs[i];
      }
    }
    if(min_cost_adjacency_label == no_label) {
      break;
    }

    is_visits[min_cost_adjacency_label] = true;

    for(int i = 0; i < matrix_graph.size(); i++) {
      if(matrix_graph[min_cost_adjacency_label][i] == infinity) {
        continue;
      }

      if(min_costs[min_cost_adjacency_label] + matrix_graph[min_cost_adjacency_label][i] < min_costs[i]) {
        min_costs[i] = min_costs[min_cost_adjacency_label] + matrix_graph[min_cost_adjacency_label][i];
      }
    }
  }

  return min_costs;
}

int main() {
  int vertex_num;
  cin >> vertex_num;
  MatrixGraph matrix_graph(vertex_num, vector<int>(vertex_num, infinity));

  for(int i = 0; i < vertex_num; i++) {
    int label, degree;
    cin >> label >> degree;
    for(int j = 0; j < degree; j++) {
      int adjacency_label;
      int adjacency_weight;
      cin >> adjacency_label >> adjacency_weight;
      matrix_graph[label][adjacency_label] = adjacency_weight;
    }
  }

  vector<int> min_consts = calc_shortest_path(matrix_graph, 0);

  for(int i = 0; i < min_consts.size(); i++) {
    cout << i << ' ' << min_consts[i] << endl;
  }
}