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>
#define MODNum 1000000007
#define WHITE  0
#define GRAY   1
#define BLACK  2
#define INFTY  2147483647
#define REP(type, i, a, b) for( type i = a; i < b; i++ )
typedef long long ll;

using namespace std;

int main (void) {
    int N;
    scanf("%d", &N);
    int u,v,k;
    int c[N][N];  /* 辺の重みを記録した隣接行列 */
    int color[N]; /* 頂点の訪問状態 */
    int d[N];     /* 最短コストの記録 */
    int p[N];     /* 最短経路木における頂点vの親 */
    int weight;
    /* Initialization */
    for ( int i = 0; i < N; i++ ){
        d[i]     = INFTY;
        color[i] = WHITE;
        p[i]     = -1;
        for ( int j = 0; j < N; j++ ) c[i][j] = INFTY;
    }
    /* グラフを読み込み */
    for ( int i = 0; i < N; i++ ){
        scanf("%d %d", &u, &k);
        for ( int j = 0; j < k; j++ ){
            scanf("%d %d", &v, &weight);
            c[u][v] = weight;
        }
    }
    /* 始点 */
    d[0]     = 0;
    color[0] = GRAY;
    int minv;

    while ( 1 ){
        minv = INFTY;
        u = -1;
        /* 確定していない値の中で最小のものを探す　*/
        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; /* 値を確定 */
        for ( v = 0; v < N; v++ ){
            if ( color[v] != BLACK && c[u][v] != INFTY ){
                /* まだ確定していない頂点との経路が存在するなら */
                if ( d[v] > d[u] + c[u][v] ){
                    /* 最短経路を探索、他にあるなら更新 */
                    d[v] = d[u] + c[u][v];
                    color[v] = GRAY;
                }
            }
        }

    }

    /* 各頂点までの最短距離 */
    for ( int i = 0; i < N; i++ ){
        printf("%d %d\n", i, d[i]);
    }

    return 0;
}

C++: //ALDS1_12B
#include <iostream>
using namespace std;

static const int MAX=100;
static const int INF=(1<<21);
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;

int n,M[MAX][MAX];

int dijkstra(){
 int minv;
 int d[MAX],color[MAX];
 for(int i=0;i<n;i++){
  d[i]=INF;
  color[i]=WHITE;
 }
 d[0]=0;
 color[0]=GRAY;
 while(true){
  minv=INF;
  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]!=INF){
    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]==INF ? -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]=INF;
  }
 }
 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;
}