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;

const long MAX = 100;
const long INFTY = (1<<21);
const long WHITE = 0;
const long GRAY = 1;
const long BLACK = 2;

long n, M[MAX][MAX];

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

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

	d[0] = 0;
	color[0] = GRAY;
	while (1){
		minv = INFTY;
		long u = -1;
		for (long 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 (long 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 (long i = 0; i < n; i++){
		cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
	}
}

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

	long k, c, u, v;
	for (long i = 0; i < n; i++){
		cin >> u >> k;
		for (long j = 0; j < k; j++){
			cin >> v >> c;
			M[u][v] = c;
		}
	}

	dijkstra();

	return 0;
}

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

#define NODE_NUM 100

class Node
{
private:
	int next_node_list[NODE_NUM];
	int next_node_num;
	int next_weight_list[NODE_NUM];
public:
	Node();
	void AddNextNode(int id, int weight);
	void SetWeight(int weight);
	void DistributeWeight();
	int weight_from_0;
	bool check;
};

Node::Node()
{
	next_node_num = 0;
	weight_from_0 = -1;
	check = false;
}

Node *Node_list;
list<int> Distributed_node_list;

void Node::AddNextNode(int id, int weight)
{
	next_node_list[next_node_num] = id;
	next_weight_list[next_node_num] = weight;
	next_node_num++;
}

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

void Node::DistributeWeight()
{
	check = true;
	for (int i = 0; i < next_node_num; i++) {
		if (Node_list[next_node_list[i]].check == false) {
			Distributed_node_list.push_back(next_node_list[i]);
			Node_list[next_node_list[i]].SetWeight(weight_from_0 + next_weight_list[i]);
		}
	}
}

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[i].AddNextNode(v, c);
		}
	}

	//weight from 0 ?
	Node_list[0].SetWeight(0);
	Node_list[0].DistributeWeight();
	while (!Distributed_node_list.empty()) {
		int min_weight = Node_list[Distributed_node_list.front()].weight_from_0;
		list<int>::iterator min_idx = Distributed_node_list.begin();
		list<int>::iterator itr;
		for(itr = Distributed_node_list.begin(); itr != Distributed_node_list.end(); itr++){
			if (Node_list[*itr].weight_from_0 < min_weight) {
				min_weight = Node_list[*itr].weight_from_0;
				min_idx = itr;
			}
		}
		Node_list[*min_idx].DistributeWeight();
		Distributed_node_list.erase(min_idx);
	}
	
	//output
	for (int i = 0; i < n; i++) {
		cout << i << " " << Node_list[i].weight_from_0 << endl;
	}
	
	return 0;
}

C++: #include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;
typedef pair<int, int> P;
#define MAX_N (105)
#define MAX_C (100010)
#define INF (MAX_N * MAX_C)
vector<P> G[MAX_N];
int dist[MAX_N];
bool arrived[MAX_N];

int main()
{
    int n;
    scanf("%d", &n);
    
    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);
	    G[u].push_back( make_pair(v, c) );
	}
    }
    
    for ( int i = 0; i < n; i++ ) {
	dist[i] = INF;
    }

    dist[0] = 0;

    while ( true ) {
	int min_dist = INF;
	int u = -1;
	for ( int i = 0; i < n; i++ ) {
	    if ( !arrived[i] ) {
		if ( min_dist > dist[i] ) {
		    min_dist = dist[i];
		    u = i;
		}
	    }
	}
	
	if ( min_dist == INF ) break;
	arrived[u] = true;

	for ( int i = 0; i < G[u].size(); i++ ) {
	    P p = G[u][i];
	    int v = p.first;
	    int c = p.second;

	    if ( !arrived[v] ) {
		dist[v] = min( dist[v], dist[u] + c );
	    }
	}
    }

    for ( int i = 0; i < n; i++ ) {
	printf("%d %d\n", i, dist[i]);
    }

    return 0;
}

C++: #include <algorithm>
#include <cstdio>
#include <iostream> 
using namespace std;  
const int maxn=105;
const int INF = 0x3f3f3f3f;   
int Map[maxn][maxn]; 
int n;
int min(int x,int y)
{
	if(x<y) return x;
	else  return y;
 } 
void floyd()  
{  
    for(int k=0;k<n;k++)  
        for(int i=0;i<n;i++)  
            for(int j=0;j<n;j++)  
            Map[i][j]=min(Map[i][j],Map[i][k]+Map[k][j]);  
}  
int main()  
{   
    scanf("%d",&n);
	     for(int i = 0 ; i<n ; i++)
			for(int j = 0 ; j<n ; j++) 
				Map[i][j] = i==j?0:INF;
    for(int i=0;i<n;i++) 
    {   int a,m;
	    scanf("%d%d",&a,&m);
        for(int i=0;i<m;i++)  
        {  
            int b,w;  
            scanf("%d%d",&b,&w);  
            Map[a][b]=Map[b][a]=min(Map[a][b],w);  
        }
    }
        floyd();
        for(int i=0;i<n;i++)
        {
        printf("%d %d\n",i,Map[0][i]); 
		}  
    return 0;  
}