Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
type Node struct {
	cost int
	done bool
}

type Edge struct {
	to, cost int
}

const INF = 1 << 60

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	nodes := make([]Node, N)
	for i := 0; i < N; i++ {
		nodes[i].cost = INF
	}
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id] = append(E[id], Edge{to, cost})
		}
	}
	nodes[0].cost = 0
	for {
		cur := 0
		minCost := INF
		for i := 0; i < N; i++ {
			n := nodes[i]
			if !n.done && n.cost < minCost {
				cur = i
				minCost = n.cost
			}
		}
		if minCost == INF {
			break
		}
		nodes[cur].done = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+nodes[cur].cost
			if !nodes[to].done && cost < nodes[to].cost {
				nodes[to].cost = cost
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, nodes[i].cost)
	}
	wtr.Flush()
}

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;  
}