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++: #include<iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];
    
    for ( int i = 0; i < n; i++ ){
        d[i] = INFTY;
        color[i] = WHITE;
    }
    
    d[0] = 0;

}

int main() {
    cin >> n;
    
    for ( int i = 0; i < n; i++ ){
        for ( int j = 0; j < n; j++ ){
            M[i][j] = INFTY;
        }
    }
    
    int k, c, u, v;
    for ( int i = 0; i < n; i++ ){
        cin >> u >> k;
        for ( int j = 0; j < k; i++ ){
            cin >> v >> c;
            M[u][v] = c;
        }
    }
    
    dijkstra();
    
    return 0;
}

C++: #include <iostream>
#include <queue>
#include <utility>
using namespace std;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int>> adj[100];
int *d;

void dijkstra() {
    priority_queue<pair<int, int>> PQ;
    int d[n], color[n];

    for (int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[n] = WHITE;
    }
    d[0] = 0;
    PQ.push(make_pair(0, 0));

    while (!PQ.empty()) {
        pair<int, int> f = PQ.top();
        PQ.pop();

        int u = f.second;
        color[u] = BLACK;

        if (d[u] < f.first * (-1)) { continue; }

        for (int j = 0; j < adj[u].size(); j++) {
            int v = adj[u][j].first;
            if (color[v] == BLACK) { continue; }
            if (d[u] + adj[u][j].second < d[v]) {
                d[v] = d[u] + adj[u][j].second;
                PQ.push(make_pair(d[v] * (-1), v));
                color[v] = GRAY;
            }
        }
    }
    
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

int main() {
    cin >> 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;
            adj[u].push_back(make_pair(v, c));
        }
    }

    dijkstra();

    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX =10000;
static const int INFTY =(1<<20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK =2;
int n;
vector<pair<int, int> > adj[MAX];

void dijkstra(){
  priority_queue<pair<int, int> >PQ;
  int color[MAX];
  int d[MAX];
  for ( int i = 0;i < n; i++) {
    d[i] =INFTY;
    color[i] =WHITE;
  }
  d[0] = 0;
  PQ.push(make_pair(0,0));
  color[0] =GRAY;
  while ( !PQ.empty()){
    pair <int, int> f= PQ.top();
    PQ.pop();
    int u=f.second;
    color[u] = BLACK;
    if(d[u] < f.first*(-1))continue;
    for (int j =0;j <adj[u].size();j++){
      int v=adj[u][j].first;
      if(color[v]==BLACK)continue;
      if(d[v] > d[u]  + adj[u][j].second){
	d[v] = d[u] + adj[u][j].second;
	PQ.push(make_pair(d[v] *(-1),v));
	color[v] =GRAY;
      }}}
  for(int i=0;i<n;i++){
    cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
  }}
int main(){
  int k,u,v,c;
  cin>>n;
  for(int i=0;i<n;i++){
    cin>> u >>k;
    for (int j =0;j < k;j++){
      cin >> v >> c;
      adj[u].push_back(make_pair(v,c));
    }}
  dijkstra();
  return 0;
}

C++: #include<bits/stdc++.h>
#define REP(i,n) for(long long i=0;i<n;++i)
#define FOR(i,a,b) for(long long i=a;i<b;++i)
#define F first
#define S second
using namespace std;

typedef pair< int,int > point;
vector< point > graph[101];
vector< int > v(101);
int n;
const int INF=1<<30;

void dijkstra(int s){
    priority_queue< point,vector< point >,greater< point > >pq;
    pq.push({0,s});
    fill(v.begin(),v.end(),INF);
    v[s]=0;
    while(!pq.empty()){
        point p=pq.top();
        pq.pop();
        REP(i,graph[p.S].size()){
            int nex=graph[p.S][i].S;
            int cost=p.F+graph[p.S][i].F;
            if(v[nex]>cost){
                v[nex]=cost;
                pq.push({cost,nex});
            }
        }
    }
}

int main(){
    scanf("%d",&n);
    int u,k,to,c;
    REP(i,n){
        scanf("%d%d",&u,&k);
        REP(j,k){
            scanf("%d%d",&to,&c);
            graph[u].push_back({c,to});
        }
    }
    dijkstra(0);
    REP(i,n){
        printf("%d ",i);
        printf("%d\n",v[i]);
    }
    return 0;
}

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

#define WHITE 0 
#define GRAY 1
#define BLACK 2
#define INFTY 10000000
int n,color[100],M[100][100],d[100],p[100];
int i,j,u,k,v,c;

void dijkstra(){
  for( i = 0; i < n; i++ ){
    color[i] = WHITE;
    d[i] = INFTY;
  }
  d[0] = 0;
  p[0] = -1;
  int cnt = 0;
  // color[0] = GRAY;
  while(1){
    cnt++;
    //cout << cnt << endl;
    int u = -1;
    int mincost = INFTY;
    for( i = 0; i < n; i++ ){
      if( color[i] != BLACK && d[i] < mincost ){
	mincost = d[i];
	u = i;
      }
    }
    if( u == -1 ) break;
    //    if( mincost == INFTY ) break;
    color[u] = BLACK;

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

  for( i = 0; i < n; i++ ){
    cout << i << " ";
    if( d[i] == INFTY ) cout << -1;
    else cout << d[i];
    cout << endl;
  }
}

int main(){
 
  cin >> n;

  for( i = 0; i < n; i++ ){
    for( j = 0; j < n; j++ ){
      M[i][j] = INFTY;
    }
  }

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

  return 0;
}