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 INF=1<<21;
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;

int n,A[MAX][MAX];

void dijkstra(){
  int color[MAX],mincost,k,p[MAX],d[MAX];

  for(int i=0;i<n;i++){
    color[i]=WHITE;
    d[i]=INF;
  }
  d[0]=0;
  p[0]=-1;
  color[0]=GRAY;

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

    for(int i=0;i<n;i++){
      if(color[i]!=BLACK && A[k][i]!=INF){
	if(d[k]+A[k][i]<d[i]){
	  d[i]=d[k]+A[k][i];
	  p[i]=k;
	  color[i]=GRAY;
	}
      }
    }
  }
  for(int i=0;i<n;i++){
    cout<<i<<" "<<(d[i]==INF ? -1:d[i])<<endl;
  }
}


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

  dijkstra();
}

C++: #include <bits/stdc++.h>
using namespace std;
static const int M=10000;
static int INF=(1<<20);
int n;
vector<pair<int,int > > a[M];
void dijkstra(){
	priority_queue<pair<int,int> > Q;
	int col[M];
	int d[M];
	for(int i=0;i<n;i++){
		col[i]=0;
		d[i]=INF;
	}
	d[0]=0;col[0]=1;
	Q.push(make_pair(0,0));
	while(!Q.empty()){
		pair<int,int>f=Q.top();Q.pop();
		int u=f.second;col[u]=2;
		if(d[u]<f.first)continue;
		for(int j=0;j<a[u].size();j++){
			int v=a[u][j].first;
			if(col[v]==2)continue;
			if(d[v]>d[u]+a[u][j].second){
				d[u]=d[u]+a[u][j].second;
				Q.push(make_pair(d[v]*(-1),v));
				col[v]=1;
			}
		}
	}
	for(int i=0;i<n;i++)cout<<i<<' '<<(d[i]==INF?-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;
			a[u].push_back(make_pair(v,c));
		}
	}
	dijkstra();
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<utility>
#include<vector>


using namespace std;



int main() {
	int n,tmp1,tmp2,size;
	int cnt_arrived=0;
	pair<int, int> ptmp;
	priority_queue<pair<int, int>,vector<pair<int,int>>,greater<pair<int,int>>> pq;
	cin >> n;
	int** mat = new int* [n];
	vector<pair<int, int>>* list_adjacent = new vector<pair<int, int>>[n];
	int* dist = new int[n];
	for (int i = 0;i < n;i++) {
		cin >> tmp1 >> size;
		for (int j = 0;j < size;j++) {
			cin >> tmp1 >> tmp2;
			list_adjacent[i].push_back(make_pair(tmp1, tmp2));
		}
		dist[i] = -1;
	}
	pq.push(make_pair(0, 0));
	while (cnt_arrived < n) {
		ptmp = pq.top();
		pq.pop();
		if (dist[ptmp.second] == -1) {
			cnt_arrived++;
			dist[ptmp.second] = ptmp.first;
			for (int i = 0;i < list_adjacent[ptmp.second].size();i++) {
				pq.push(make_pair(ptmp.first + list_adjacent[ptmp.second][i].second, list_adjacent[ptmp.second][i].first));
			}
		}
	}
	for (int i = 0;i < n;i++) {
		cout << i << " " << dist[i] << endl;
	}
}

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

static const int MAX=100;
static const int INFTY=numeric_limits<int>::max();

typedef enum {
    WHITE,
    GRAY,
    BLACK,
}Color;

int n,M[MAX][MAX];

void Dijkstra(){
    int minv;
    int d[MAX];
    Color color[MAX];

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

    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;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define MAX 100
#define INF (1<<30)

using namespace std;
enum state{
  BLACK,
  WHITE
};

int main(){
  vector<int> v[MAX];
  vector<int> c[MAX];
  state s[MAX];
  int d[MAX];
  int n; cin>>n;

  for(int i=0;i<n;i++){
    int u; cin>>u;
    int k; cin>>k;
    for(int j=0;j<k;j++){
      int tmp,tmp2; cin>>tmp>>tmp2;
      v[u].push_back(tmp);
      c[u].push_back(tmp2);
    }
  }

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

  vector<int> blacklist;
  blacklist.push_back(0);

  while(1){
    int& last = blacklist.back();
    for(int i = 0;i<v[last].size();i++){
      if(d[v[last][i]]>d[last]+c[last][i]){
        d[v[last][i]]=d[last]+c[last][i];
      }
    }

    int minv=-1;
    int mind=INF;
    for(int b:blacklist){
      for(int i=0;i<v[b].size();i++){
        if(s[v[b][i]]!=BLACK && d[v[b][i]]<mind){
          minv=v[b][i];
          mind=d[v[b][i]];
        }
      }
    }
    if(minv!=-1){
      s[minv]=BLACK;
      blacklist.push_back(minv);
    }else{
      break;
    }
  }

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