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>
#include<cstdio>
#define W 0
#define G 1
#define B 2
#define inf 1000000
#define MAX 100
#define NIL -1
using namespace std;

int n;
int A[MAX][MAX];

void Prim(){
    int color[MAX],d[MAX],p[MAX];
    int min,u;
    for(int i = 0; i < n; i++){
        color[i] = W;
        d[i] = inf;
        p[i] = NIL;
    }
    
    d[0] = 0;
    
    while(1){
        u = -1;
        min = inf;
        for(int i = 0; i < n; i++){
            if(d[i] < min && color[i] != B){
                u = i;
                min = d[i];
            }
        }
        
        if(u == -1) break;
            
        color[u] = B;
            
        for(int i = 0; i < n; i++){
            if(color[i] != B && A[u][i] != NIL){
                if(A[u][i] + d[u] < d[i]){
                    d[i] = A[u][i] + d[u];
                    color[i] = G;
                    p[i] = u;
                }
            }
        }
    }
    
    for (int i = 0; i < n; i++){
        printf("%d %d\n",i,d[i]);
    }
}

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

C++: // -*- mode:c++; coding:utf-8; c-basic-offset:2; -*-
// ALDS1_12_B: Single Source Shortest Path I

#include <algorithm>
#include <cstdio>

using uint = unsigned int;

class Graph {
  const uint n_;
  uint* const g_;
  const uint INFINIT;
  
public:

  Graph(uint n) : n_(n), g_(new uint[(n_*n_)]), INFINIT(100000*n_) {
    std::fill_n(g_, (n_*n_), INFINIT);
  }

  ~Graph() { delete[] g_; }
  
  uint* operator [](uint i) const { return g_+(n_*i); }

  void dijkstra(uint* dist)
  {
    std::fill_n(dist, n_, INFINIT);
    bool visited[n_];
    std::fill_n(visited, n_, false);
    auto i = 0u; // 0-start
    visited[i] = true;
    dist[i] = 0u;
    for (auto n = 0u; n < n_-1; ++n) {
      auto cur_min = INFINIT;
      auto es = (*this)[i];
      auto base_dist = dist[i];
      for (auto j = 0u; j < n_; ++j) {
        if (visited[j]) continue;
        dist[j] = std::min(dist[j], base_dist+es[j]);
        if (cur_min > dist[j]) {
          cur_min = dist[j];
          i = j;
        }
      }
      visited[i] = true;
      dist[i] = cur_min;
    }
  }
};

int main()
{
  uint n;
  std::scanf("%u", &n);

  Graph g(n);

  uint u, k, c, v;
  for (auto i = 0u; i < n; ++i) {
    std::scanf("%u %u", &u, &k);
    for (auto j = 0u; j < k; ++j) {
      std::scanf("%u %u", &c, &v);
      g[u][c] = v;
    }
  }

  uint dist[n];
  g.dijkstra(dist);
  for (auto i = 0u; i < n; ++i) {
    std::printf("%u %u\n", i, dist[i]);
  }
}

// eof

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;
    color[0]=gray;
    while(1){
	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<bits/stdc++.h>
#define pb push_back
using namespace std;
long long dis[10002];
bool vis[10002];
vector<int> a[10002];
vector<int> b[10002];
int n,u,k,x,t=1,w,m,s,v;
queue<int> q;
int main(){
	cin>>n;
	memset(vis,false, sizeof(vis));
	memset(dis,0x1f1f1f1f,sizeof(dis));
	for (int i=0; i<n; i++){
		cin>>u>>k;
		while (2*k--){
			  cin>>v>>w;
			  a[u].pb(v);
		      b[u].pb(w);
		}
	}
	q.push(0);
	dis[0]=0;
	while (!q.empty()){
		  x=q.front(); q.pop(); vis[x]=false;
		  for (int i=0; i<a[x].size(); i++){
		  	  if (dis[a[x][i]]>dis[x]+b[x][i]){
		  	  	  dis[a[x][i]]=dis[x]+b[x][i];
		  	  	  if (!vis[a[x][i]]){
		  	  	  	  vis[a[x][i]]=true;
		  	          q.push(a[x][i]);
                  }
			 }
		  	  
		  }
	}
    for (int i=0; i<n; i++){
		cout<<i<<' '<<dis[i]<<'\n';
	}
	return 0;
}