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<bits/stdc++.h>
using namespace std;

typedef pair<int, int> P;
const int M = 1000000007;

vector<int> dijkstra(int s, vector<vector<P>> edge) {
    int n = edge.size();
    vector<int> dist(n, M);
    priority_queue<P, vector<P>, greater<P>> q;
    dist[s] = 0;
    q.push(P(0, s));
    while (!q.empty()) {
        P p = q.top();
        q.pop();
        int d = p.first;
        for (auto& e : edge[p.second]) {
            if (dist[e.second] > p.first + e.first) {
                dist[e.second] = p.first + e.first;
                q.push(P(p.first + e.first, e.second));
            }
        }
    }
    return dist;
}


int main() {
    int n;
    cin >> n;
    vector<vector<P>> edge(n);
    for (int i = 0; i < n; ++i) {
        int u, k;
        cin >> u >> k;
        if (i != u) exit(1);
        for (int j = 0; j < k; ++j) {
            int v, c;
            cin >> v >> c;
            edge[i].push_back(P(c, v));
        }
    }
    vector<int> d = dijkstra(0, edge);
    for (int i = 0; i < n; ++i) {
        cout << i << " " << d[i] << "\n";
    }
    return 0;
}

C++: #include<iostream>
using namespace std;
#define N 105
#define INF 1<<21
int n;
int a[N][N];
int d[N],p[N];
int color[N];
void dijksla(){
	int minv;
	for (int i = 0;i < n;i++){
		d[i] = INF;
		color[i] = 0;
	}
	d[0] = 0;
	while (1){
		minv = INF;
		int u = -1;
		for (int i = 0;i < n;i++){
			if (minv > d[i] && color[i] != 1){
				u = i;
				minv = d[i];
			}
		}
		if (u == -1) break;
		color[u] = 1;
		for (int v = 0;v < n;v++){
			if (color[v] == 0 && a[u][v] != INF){
				if (d[v] > d[u] + a[u][v]){
					d[v] = d[u] + a[u][v];
				}
			}
		}
	}
	for (int i = 0;i < n;i++){
		if (d[i] == INF){
			cout << i << " -1" << endl;
		}
		else{
			cout << i << " " << d[i] << endl;
		}
	}
}

int main()
{
	cin >> n;
	for (int i = 0;i < n;i++){
		for (int j = 0;j < n;j++){
			a[i][j] = INF;
		}
	} 
	int x,m,y,q;
	for (int i = 0;i < n ;i++){
		cin >> x >> m;
		for (int j = 0;j < m;j++){
			cin >> y >> q;
			a[x][y] = q;
		}
	}
	dijksla();
	return 0;
 }

C++: #include <bits/stdc++.h>
using namespace std;

int n;
int MAXIMUM=100;
int M[100][100];
int INF = 123456789;
// W:未訪問
// G:訪問する候補
// B:訪問済み
int W=0,G=1,B=2;
int dijkstra(){
  int u,minv;
  int d[MAXIMUM],color[MAXIMUM];
  // d[n]:Tに属する頂点と V - T に属する頂点をつなぐ辺の中で重みが最小の辺の重みを記録
  // p[i]: 頂点iからコスト最小となる親の頂点
  //初期化
  for(int i=0;i<n;i++){
    d[i]=INF;
    color[i]=W;
  }

  d[0]=0;
  color[0] = G;

  while (1) {
    minv = INF;
    u = -1;
    //訪問済みでない頂点の中で最もコストが低い辺を探す
    for(int i=0;i<n;i++){
      if(minv>d[i] && color[i]!=B){
        u=i;
        minv=d[i];
      }
    }
    // 頂点が見つからなかったら終了
    if(u==-1) break;
    // 頂点を訪問済に
    color[u] = B;
    //訪問済みでないかつ辺がつながっている頂点の中でコストが最小の辺を選択
    for(int v=0;v<n;v++){
      if(color[v]!=B && M[u][v]!=INF){
        if(d[v]>M[u][v] + d[u]){
          d[v] =M[u][v]+d[u];
          color[v]=G;
        }
      }
    }
  }

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

int main(){
  cin>>n;
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      M[i][j]=INF;
    }
  }

  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;
      M[u][v]=c;
    }
  }

  dijkstra();

}

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 <climits>
#include <functional>
#include <iostream>
#include <queue>
#include <utility>
#include <vector>
using namespace std;

int main() {
	int n, u, k, v, c;
	cin >> n;
	vector<vector<pair<int, int>>> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> u >> k;
		for (int j = 0; j < k; ++j) {
			cin >> v >> c;
			a[u].emplace_back(v, c);
		}
	}
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> b;
	b.emplace(0, 0);
	vector<bool> d(n);
	vector<int> e(n, INT_MAX);
	e[0] = 0;
	while (!b.empty()) {
		pair<int, int> f = b.top();
		b.pop();
		d[f.second] = true;
		for (int i = 0; i < a[f.second].size(); ++i) {
			if (!d[a[f.second][i].first]) {
				if (a[f.second][i].second + e[f.second] < e[a[f.second][i].first]) {
					e[a[f.second][i].first] = a[f.second][i].second + e[f.second];
					b.emplace(e[a[f.second][i].first], a[f.second][i].first);
				}
			}
		}
	}
	for (int i = 0; i < n; ++i) cout << i << ' ' << e[i] << endl;
}