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 <vector>
#define INF 1<<30
#define WHITE 0
#define GRAY 1
#define BLACK 2
int G[101][101];
using namespace std;
int n;

void prim(int *d, int *pi){
    int color[n];
    int u = 0;
    for (int i = 0; i < n; i++){
        d[i] = pi[i] = INF;
        color[i] = WHITE;
    }
    d[0] = 0;
    while (1){
        int mincost = INF;
        for (int i = 0; i < n; i++){
            if (color[i] != BLACK && d[i] < mincost){
                mincost = d[i];
                u = i;
            }
        }
        if (mincost == INF) break;
        color[u] = BLACK;
        for (int v = 0; v < n; v++){
            int w = G[u][v];
            if (w == -1) continue;
            else if (color[v] != BLACK && d[u]+w < d[v]){
                pi[v] = u;
                d[v] = d[u] + w;
            }
        }
    }
}

int main(int argc, char* argv[]) {
    cin >> n;
    int d[n], pi[n], sum = 0;
    int u, k, v, c;

    //initialize
    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            G[i][j] = -1;
        }
    }
    //input
    for (int i = 0; i < n; i++){
        cin >> u >> k;
        for (int j = 0; j < k; j++){
            cin >> v >> c;
            G[u][v] = c;
        }
    }
    prim(d, pi);
    for (int i = 0; i < n; i++){
        cout << i << " " << d[i] << endl;
    }
    return 0;
}

C++: #include <iostream>

using namespace std;

#define MAX 100
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define INFTY 999999999999999

int color[MAX];
int M[MAX][MAX];
int d[MAX];
int p[MAX];
int n;

int dijkstra(int s)
{

	int mincost;
	int u;

	for (int i = 0; i < n; i++) {
		d[i] = INFTY;
		p[i] = -1;
	}
	d[s] = 0;

	while (true) {
		mincost = INFTY;

		for (int i = 0; i < n; i++) {
			if (color[i] != BLACK&&d[i] < mincost) {
				mincost = d[i];
				u = i;
			}
		}

		if (mincost == INFTY) {
			break;
		}

		color[u] = BLACK;

		for (int i = 0; i < n; i++) {
			if (color[i] != BLACK&&M[u][i] != -1) {
				if (d[u] + M[u][i] < d[i]) {
					d[i] = d[u] + M[u][i];
					p[i] = u;
					color[i] = GRAY;
				}
			}
		}


	}


	int sum = 0;

	for (int i = 0; i < n; i++) {
		sum += d[i];
	}

	return sum;


}

int main(void)
{

	cin >> n;

	int u;
	int k;
	int v;

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

	for (int i = 0; i < n; i++) {
		cout << i << " " << dijkstra(i) << endl;
	}

	return 0;
}

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

int n;
const int INF = 1000000;
vector<vector<int> > v, c;
vector<int> w;

void trip(int id, int dp) {
	if (dp > n)
		return;

	for (int j = 0; j < (int)v[id].size(); j++) {
		if (w[v[id][j]] > w[id] + c[id][j])
			w[v[id][j]] = w[id] + c[id][j];
		trip(v[id][j], dp + 1);
	}
}

int main()
{
	cin >> n;

	int u, k, v1, c1;
	v.resize(n);
	c.resize(n);
	w.assign(n, INF);

	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v1 >> c1;
			v[u].push_back(v1);
			c[u].push_back(c1);
		}
	}

	w[0] = 0;
	trip(0, 1);

	for (int i = 0; i < n; i++)
		cout << i << " " << w[i] << endl;

	return 0;
}

C++: //専用ライブラリ
#include <iostream>
#include <iomanip>
#include <istream>
#include <ostream>
#include <sstream>
#include <iterator>
#include <vector>
#include <algorithm>
#include <queue>
#include <deque>
#include <list>
#include <stack>
#include <map>
#include <set>
#include <utility>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <string>
#include <ctime>
#include <cctype>
#include <cstdlib>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll>P;
#define INF 10e6
#define MOD 1000000007
#define rep(i, a, n) for (ll i = a; i < (ll)(n); i++)
#define fi first
#define se second
#define mmax(x,y)(x>y?x:y)
#define mmin(x,y)(x<y?x:y)
#define PI acos(-1.0)
long long GCD(long long a, long long b) { return b ? GCD(b, a%b) : a; }
long long LCM(long long a, long long b)  {return a/GCD(a,b)*b;}
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};
int cmp(P a,P b){
        if(a.fi!=b.fi)
        return a.fi>b.fi;
        else
        return a.se<b.se;
}
//---------------------------------------------------------------------------
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define N 100005

int n,M[101][101];

void dijkstra(){
    int minv;
    int d[101],color[101];
    
    for(int i=0;i<n;i++){
        d[i]=INF;
        color[i]=WHITE;
    }
    d[0]=0;
    color[0]=GRAY;
    while(1){
        minv=INF;
        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)//没有点了
            break;
        color[u]=BLACK;
        for(int v=0;v<n;v++){
            if(color[v]!=BLACK&&M[u][v]!=INF){
                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]==INF ? -1 : d[i])<<endl;
    }
}
//---------------------------------------------------------------------------
int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    //-------------------------------
    cin>>n;
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++){
            M[i][j]=INF;
        }
    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;
}
//---------------------------------------------------------------------------