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>

struct Edge {
	int to, weight;
};

int main()
{
	int n, u, k, v, c, distance[100]{}, upd_num = 1;
	bool must_update[100]{ 1 };
	std::vector<Edge> dest[100];

	std::cin >> n;
	for (int i = 0; i < n; ++i)
	{
		std::cin >> u >> k;
		for (int j = 0; j < k; ++j)
		{
			std::cin >> v >> c;
			dest[u].push_back({ v, c });
		}
		if (i)
			distance[i] = 2000000000;
	}

	while (upd_num)
		for (int i = 0; i < n && upd_num; i++)
		{
			if (!must_update[i]) continue;

			must_update[i] = false;
			upd_num--;
			for (auto e : dest[i])
			{
				int tmp = distance[i] + e.weight;
				if (tmp < distance[e.to])
				{
					distance[e.to] = tmp;
					if (!must_update[e.to])
					{
						must_update[e.to] = true;
						upd_num++;
					}
				}
			}
		}

	for (int i = 0; i < n; i++)
	{
		std::cout << i << " " << distance[i] << std::endl;
	}

	return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s) {
	for (int i = 0; i < V; i++) {
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;
	while (true) {
		int v = -1;
		for (int u = 0; u < V; u++) {
			if (!used[u] && ((v == -1) || d[u] < d[v])) {
				v = u;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		used[v] = true;
		for (int u = 0; u < V; u++) {
			d[u] = min(d[u], d[v] + cost[v][u]);
		}
	}
}

int main() {
	for (int i = 0; i < V; i++) {
		for (int j = 0; j < V; j++) {
			cost[i][j] = INF;
		}
	}
	cin >> V;
	for (int i = 0; i < V; i++) {
		int u;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;
		}
	}
	dijkstra(0);

	for (int i = 0; i < V; i++) {
		cout << i << " " << d[i] << endl;
	}
	return 0;
}

C++: #include <cstdio>
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, **M;
int *d;

void dijkstra() {
    int u, minv;
    int d[n], color[n];

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

    while (1) {
        u = -1;
        minv = INFTY;
        for (int i = 0; i < n; i++) {
            if (color[i] != BLACK && d[i] < minv) {
                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[u] + M[u][v] < d[v]) {
                    d[v] = d[u] + M[u][v];
                    color[v] = GRAY;
                }             
            }
        }
    }
    
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

int main() {
    scanf("%d", &n);

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

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

    dijkstra();

    return 0;
}

C++: #include<iostream>
using namespace std;
static const int N = 100;
static const int INF = 10000000;
static const int WHITE =0;
static const int GRAY =1;
static const int BLACK =2;

int n,A[N][N]; //隣接行列

void dijkstra(){
    int min ;
    int d[N],color[N];

    for(int i =0;i<n;i++){
        d[i] = INF;
        color[i] =WHITE;
    }
    d[0] =0;
    color[0] = GRAY;
    while(1){
        min = INF;
        int u = -1;
        for(int i =0;i <n;i++){
            if(min > d[i] && color[i] != BLACK){
                u = i;
                min  = d[i];
            }
        }
        if(u ==-1) break;
        color[u] = BLACK;
        for(int v =0;v<n;v++){
            if(color[v] != BLACK && A[u][v] != INF){
                if(d[v] > d[u] + A[u][v]){
                    d[v] = d[u] + A[u][v];
                    color[v] =GRAY; 
                }
            }
        }
    }

    for(int i = 0;i<n;i++){
        cout<< i << " "<< (d[i] == INF ? -1 :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 k,c,u,v;
    for(int i =0;i<n;i++){
        cin >> u >> k;
        for(int j =0;j<k;j++){
            cin >> v >> c;
            A[u][v] = c;
        }
    }

    dijkstra();

    return 0;
}

C++: #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <limits.h>


#define MAX_E 20
#define MAX_V 7
#define INF 100000

typedef struct edge{
    int from;
    int to;
    int cost;
}edge;


edge es[MAX_E];

int distance[MAX_V];

void bellman_ford(int n, int s, int e) {
    int i, update;
    
    for (int i = 0; i < MAX_V; i++) distance[i] = INF;
    distance[s] = 0;
    while (1) {
        update = 0;
        for (i = 0; i < e; i++) {
            edge e = es[i];
            if (distance[e.from] != INF && distance[e.to] > distance[e.from] + e.cost) {
                distance[e.to] = distance[e.from] + e.cost;
                update = 1;
            }
        }
        if (!update) break;
    }
}


int main( ){
    
    int n, i, j, l, u, v, k, c;
    scanf("%d", &n);
    
    
    l = 0;
    for (i = 0; i < n; i++) {
        scanf("%d %d", &u, &k);
        
        for (j =0 ; j < k; j++) {
            scanf("%d %d", &v, &c);
            es[l].from = u;
            es[l].to = v;
            es[l].cost = c;
            l++;
        }
    }
    
    bellman_ford(n, 0, l);
    
    for (i=0; i<n; i++) {
        printf("%d %d\n", i, distance[i]);
    }
    
    return 0;
}