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<bits/stdc++.h>
using namespace std;

#define MAX 100
#define BLACK 0
#define GRAY 1
#define WHITE 2
#define INF (1<<30)

int graph[MAX][MAX];
int n;

// プロトタイプ宣言
void dijkstra(int start);
// ここまで

int main(){
	for(int i=0;i<MAX;i++){
		for(int j=0;j<MAX;j++){
			graph[i][j]=INF;
		}
	}

	int from,to,k,weight;		cin>>n;
	for(int i=0;i<n;i++){
		cin>>from>>k;
		for(int j=0;j<k;j++){
			cin>>to>>weight;
			graph[from][to]=weight;
		}
		
	}

	dijkstra(0);

	return 0;
}

//  - - - - - - - - - - - - - - - - - - - --
void dijkstra(int start){
	int color[MAX];
	int d[MAX];
	int p[MAX];
	for(int i=0;i<MAX;i++){
		color[i]=WHITE;
		d[i]=INF;
		p[i]=-1;
	}

	d[start]=0;
	p[start]=-1;

	while(1){
		int from = -1;
		int minCost=INF;
		for(int i=0;i<n;i++){
			if(color[i]!=BLACK && d[i]<minCost){
				minCost=d[i];
				from=i;
			}
		}
		if(from == -1)break;
		
		color[from]=BLACK;

		for(int to=0;to<n;to++){
			if(color[to]!=BLACK && graph[from][to]!=INF){
				if(d[from]+graph[from][to] < d[to]){
					d[to] =d[from]+graph[from][to];
					p[to]=from;
					color[to]=GRAY;
				}
			}
		}
	}

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

C++: #include<cstdio>

const static int MAX = 100;
const static int WHITE = 0;
const static int GRAY = 1;
const static int BLACK = 2;
const static int INFTY = (1<<30);

int M[MAX][MAX];
int color[MAX];
int d[MAX];
int p[MAX];
int n;

void dijkstra()
{
	//初始化
	for(int i=0; i<n; i++)
	{
		color[i] = WHITE;
		d[i] = INFTY;
	}
	int u;
	int mincost;
	d[0] = 0;
	p[0] = -1;

	while(1)
	{
		//选出d[u]最小的点
		mincost = INFTY;
		for(int i=0; i<n; i++)
		{
			if(color[i] != BLACK && mincost > d[i])
			{
				mincost = d[i];
				u = i;
			}
		}
		color[u] = BLACK;

		if(mincost == INFTY) break;

		for(int i=0; i<n; i++)
		{
			if(color[i] != BLACK && M[u][i] < INFTY)
			{
				if(d[u] + M[u][i] < d[i])
				{
					d[i] = d[u] + M[u][i];
					p[i] = u;
					color[i] = GRAY;
				}
			}
		}
	}
}

int main()
{
	scanf("%d", &n);
	for(int i=0; i<n; i++)
	{
		for(int j=0; j<n; j++)
			M[i][j] = INFTY;
	}
	int u,k,v,c;
	for(int i=0; i<n; i++)
	{
		scanf("%d%d", &u, &k);
		for(int j=0; j<k; j++)
		{
			scanf("%d%d", &v, &c);
			M[u][v] = c;
		}
	}

	dijkstra();

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

	return 0;
}

C++: //Single Source Shortest Path I
#include <iostream>
#include <vector>
#include <climits>

using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int BLACK = 1;
//int colors[N], d[N];
//
//void dijkstra(vector<vector<int>> &W, int n) {
//    int u, mind;
//    for(int i = 0; i < n; i++) {
//        colors[i] = WHITE;
//        d[i] = INT_MAX;
//    }
//    d[0] = 0;
//    while(1) {
//        u = -1;
//        mind = INT_MAX;
//        for(int i = 0; i < n; i++) {
//            if(colors[i] == WHITE && d[i] < mind) {
//                u = i;
//                mind = d[i];
//            }
//        }
//        if(u == -1) break;
//        colors[u] = BLACK;
//        for(int i = 0; i < n; i++) {
//            if(W[u][i] != -1) {
//                d[i] = min(d[i], mind + W[u][i]);
//            }
//        }
//    }
//}
int d[N];

void dijkstra(vector<vector<int>> &W, int n) {
    int colors[n];
    for(int i=0; i<n; i++) {
        colors[i] = WHITE;
        d[i] = INT_MAX;
    }
    
    d[0] = 0;

    while(1) {
        int u = -1;
        int min_distance = INT_MAX;
        for(int i=0; i<n; i++) {
            if(colors[i] == BLACK) continue;
            if(d[i] < min_distance) {
                u = i;
                min_distance = d[i];
            }
        }
        if(u == -1) break;

        colors[u] = BLACK;
        for(int i=0; i<n; i++) {
            if(colors[i] == BLACK) continue;
            if(W[u][i] == -1) continue;
            d[i] = min(d[i], d[u] + W[u][i]);
        }
    }
}

int main() {
    int n;
    int u, k, v, c;
    cin >> n;
    vector<vector<int>> W(n, vector<int>(n));
    for(int i = 0; i < n; i++)
        for(int j = 0; j < n; j++)
            W[i][j] = -1;
    for(int i = 0; i < n; i++) {
        cin >> u >> k;
        for(int j = 0; j < k; j++) {
            cin >> v >> c;
            W[u][v] = c;
        }
    }

    dijkstra(W, n);

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