Go: // ダイクストラのアルゴリズム
package main

import (
	"bufio"
	"fmt"
	"log"
	"math"
	"os"
	"strconv"
	"strings"
)

type color int

const (
	white color = iota // 未訪問
	mst                // MSTとして確定
)

// 頂点
type node struct {
	num       int         // 頂点の番号
	weights   map[int]int // 重みMAP
	parent    *node       // MSTへの重み最小の親
	distFromS int         // 始点からの距離
	color     color
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	n := eGetInt(scanner)

	nodes := make([]*node, n)
	for i := 0; i < n; i++ {
		weights := eAtoi((strings.Fields(eGetline(scanner))))
		v := &node{weights[0], make(map[int]int, weights[1]), nil, math.MaxInt32, white}
		for j := 0; j < weights[1]; j++ {
			k := weights[j*2+2] // 相手の頂点名
			w := weights[j*2+3] // 重み
			v.weights[k] = w
		}
		nodes[i] = v
	}

	// 初回はnode[0]がMSTに入るように
	nodes[0].distFromS = 0

	for { // 全部チェックするまで

		// どの頂点を新たにMSTに取り込むか

		var minNode *node
		min := math.MaxInt32
		for _, v := range nodes {
			if v.color == mst {
				continue
			}
			if v.distFromS < min {
				min = v.distFromS
				minNode = v
			}
		}
		if minNode == nil {
			// すべて完了している.
			break
		}

		// MSTに追加する頂点決定
		minNode.color = mst

		// fmt.Printf(">[%v]\n", minNode)
		// MSTに属していない頂点それぞれについて,Startからの最小の重みの距離を更新
		for i, v := range nodes {
			if v.color == mst {
				continue
			}
			w, ok := minNode.weights[i]
			if !ok {
				// minNodeと接してない
				continue
			}

			if minNode.distFromS+w < v.distFromS {
				// minNode経由の距離がもっとも重みが少ないので親を変更
				v.distFromS = minNode.distFromS + w
				v.parent = minNode
				// fmt.Printf("[%v %v]\n", v, minNode)
			}
		}
		// fmt.Printf("<\n")
	}

	for i, v := range nodes {
		fmt.Printf("%d %d\n", i, v.distFromS)
	}
}

func eGetInt(scanner *bufio.Scanner) int {
	t := eAtoi(strings.Fields(eGetline(scanner)))
	return t[0]
}

func eGetline(p *bufio.Scanner) string {
	if !p.Scan() {
		if err := p.Err(); err != nil {
			log.Fatal(err.Error())
		}
		return ""
	}
	return p.Text()
}

func eAtoi(s []string) []int {
	ints := make([]int, len(s))
	var err error
	for i, e := range s {
		ints[i], err = strconv.Atoi(e)
		if err != nil {
			log.Fatal(err.Error())
		}
	}
	return ints
}

C++: // #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(v) v.begin(), v.end()
#define Graph vector< vector<P> >
typedef long long ll;
typedef pair<int, int> P;
const int INF = 1000000007;

int main(){
    int N;
    cin >> N;
    Graph M(N);
    rep(i, N){
        int u, k;
        cin >> u >> k;
        rep(j, k){
            int v, c;
            cin >> v >> c;
            M[u].push_back(P(v, c));
        }
    }

    vector<int> d(N, INF), p(N, -1);
    vector<bool> seen(N, false);
    d[0] = 0;

    while(1){
        int mincost = INF;
        int u;

        rep(i, N){
            if(!seen[i] && d[i] < mincost){
                mincost = d[i];
                u = i;
            }
        }

        if(mincost == INF) break;
        seen[u] = true;

        rep(i, M[u].size()){
            int v = M[u][i].first, c = M[u][i].second;
            if(!seen[v] && d[u] + c < d[v]){
                d[v] = d[u] + c;
                p[v] = u;
            }
        }
    }

    rep(i, N){
        cout << i << ' ' << d[i] << endl;
    }

}

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

#define MAX 100
#define INF 2097152
#define WHITE 0
#define GRAY 1
#define BLACK 2

int n,M[MAX][MAX];


int main(void){

	int i,j;
	int minv,d[MAX],color[MAX];
	int u,v;

	scanf("%d",&n);
	for(i=0;i<n;i++){
		for(j=0;j<n;j++){
			M[i][j] = INF;
		}
	}

	int k,l,m,p;
	for(i=0;i<n;i++){
		scanf("%d %d",&m,&k);
		for(j=0;j<k;j++){
			scanf("%d %d",&p,&l);
			M[m][p] = l;
		}
	}

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

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

	while(1){
		minv = INF;
		u = -1;
		for(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(v=0;v<n;v++){
			if(d[v]>d[u] + M[u][v]){
				d[v] = d[u] + M[u][v];
				color[v] = GRAY;
			}
		}
	}

	for(i=0;i<n;i++){
		if(d[i] == INF){
			printf("%d -1\n",i);
		}else{
			printf("%d %d\n",i,d[i]);
		}
	}

return 0;

}

C++: #include <stdio.h>
#define INF (1<<21)

int main(void)
{
 int i,j,n,m,u,k,l,v,c,a[10000],b[10000],d[10000][10000];

 scand("%d",&n);
 
 for(i=0;i<n;i++){
 	scanf("%d %d",&u,&k);
 	a[i]=INF;
 	b[i]=0;
 	for(j=0;j<k;j++){
 		scanf("%d %d",&v,&c);
 		d[u][v]=c;
 	}
 }
 a[0]=0;
 
 while(1){
 	
 	l=-1;
 	m=INF;
 	
 	for(i=0;i<n;i++){
 		if(a[i]<m && b[i]=0){
 			m=a[i];
 			l=i;
 		}
 	}
 	
 	if(l==-1) break;
 	
 	b[l]=1;
 	
 	for(i=0;i<n;i++){
 		if(a[i]>=d[l][i]+a[l]) a[i]=d[l][i]+a[l];
 	}
 }
 
 for(i=0;i<n;i++){
 	if(a[i]==INF) printf("%d -1\n",i);
 	else printf("%d %d\n",i,a[i]);
 }
 
 return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#define INF 200001 
using namespace std;
int n;
int A[1000][1000];
int D[1000][1000];
 
void Init(int f){
  for(int i=0;i<f;i++){
    for(int j=0;j<f;j++)D[i][j] = INF;
  } 
}
 
int main(){
  scanf("%d",&n);
  int u,k,C,V;
  Init(n);
  
  for(int i=0;i<n;i++){
      scanf("%d %d",&u,&k);    
      for(int j=0;j<k;j++){
    scanf("%d %d",&V,&C);
    D[u][V] = C;
    D[V][u] = C;
      }    
  }
   
  for(int i=0;i<n;i++)D[i][i] = 0;
  for(int k=0;k<n;k++)for(int i=0;i<n;i++)for(int j=0;j<n;j++)D[i][j] = D[j][i] = min(D[i][j],D[i][k] + D[k][j]);

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