Go: package main

import (
	"strconv"
	"fmt"
	"bufio"
	"os"
)
const INF = 1 << 21
var scanner = bufio.NewScanner(os.Stdin)

func nextInt() int {
	scanner.Scan()
	i, e := strconv.Atoi(scanner.Text())
	if e != nil {
		panic(e)
	}
	return i
}


func main() {
	scanner.Split(bufio.ScanWords)
	n := nextInt()
	adj := make([][]int, n)
	for i := range adj {
		adj[i] = make([]int, n)
	}

	for i := 0;i < n; i++ {
		u := nextInt()
		k := nextInt()
		for j := 0; j < k; j++ {
			v := nextInt()
			c := nextInt()
			adj[u][v] = c
		}
	}

	// for i := range adj {
	// 	fmt.Println(adj[i])
	// }

	dist := make([]int, n)
	prev := make([]int, n)
	visited := make([]bool, n)
	dijkstra := func(start int, size int) {
		for i := 0; i < size; i++ {
			dist[i] = INF
			prev[i] = -1
			visited[i] = false
		}
		dist[start] = 0
		for {
			u := -1
			tmp_min := INF
			for i := 0; i < size; i++ {
				if visited[i] == false && dist[i] < tmp_min {
					tmp_min = dist[i]
					u = i
				}
			}
			if u == -1 {
				break
			}
			visited[u] = true
			for i := 0; i < size; i++ {
				if adj[u][i] > 0 {
					w := adj[u][i]
					newlen := dist[u] + w
					if newlen < dist[i] {
						dist[i] = newlen
						prev[i] = u
					}
				}
			}
		}
	}
	dijkstra(0, n)
	for i, cost := range dist {
		fmt.Printf("%d %d\n", i, cost)
	}
}

C++: #include"iostream"
#include"algorithm"
#include"cstdio"
#include"cstring"
#include"string"
#include"vector"
#include"queue"
#include"map"
#include"set"
#include"stack"
#include"cmath"
using namespace std;
#define INF 0xfffffff
#define maxn 10002
struct Node
{
    int e;
    int w;
    friend bool operator < (Node A, Node B)
    {
        return  A.w > B.w;
    }
};
bool vis[maxn];
int m, n;
vector< vector<Node> > G;
int Dij(int S,int E)
{
    Node P, Pn;
    P.e = S;
    P.w = 0;
	priority_queue<Node> Q;
	Q.push(P);
	while( !Q.empty() )
    {
        P = Q.top();
        Q.pop();
		if( vis[P.e] )
            continue;
		vis[P.e] = true;
		if( P.e == E )
            return P.w;
		int len = G[P.e].size();
		for(int i=0; i< len; i++)
        {
            Pn.e = G[P.e][i].e;
            Pn.w = G[P.e][i].w + P.w;
			if( !vis[Pn.e] )
                Q.push(Pn);
        }
    }
    return -1;
}
int main()
{
		Node P;
		cin >> m;
        G.resize(10000+1);
		for(int i=0; i<m; i++)
        {
			int k;
			memset(vis,false,sizeof(vis));
			scanf("%d%d",&n,&k);
			for(int j=0;j<k;j++)
			{
            int  b, c;
            cin >> b >> c;
            P.e = b;
            P.w = c;
            G[n].push_back(P);
            P.e = n;
            G[b].push_back(P);
			}
			}
			for(inti=0;i<m;i++)
			{
			int ans = Dij(0,n);
			printf("%d %d\n",n,ans);
        }
    return 0;
}

C++: #include <iostream>
using namespace std;
#define MAX 100
#define INFTY 1<<22
#define WHITE 0
#define GRAY 1
#define BLACK 2

int gMatrix[MAX][MAX];

void dijkstra(int n){
    // 最小の重みを記録する
    int minV;
    // weight[v]に始点sからvまでの最短コストを保存する
    int weight[MAX];
    // 訪問状態を記録
    int color[MAX];
    // 1.初期化
    for(int i = 0;i < n;++i){
        weight[i] = INFTY;
        color[i] = WHITE;
    }
    // 始点
    weight[0] = 0;
    color[0] = GRAY;
    
    while(1){
        minV = INFTY;
        // 頂点を示す
        int u = -1;
        // 2.1weight[u]が最小である頂点を決定する
        for(int i = 0;i < n;++i){
            if(minV > weight[i] && color[i] != BLACK){
                u = i;
                minV = weight[i];
            }
        }
        if(u == -1)break;
        color[u] = BLACK;
        
        for(int v = 0;v < n;++v){
            // 辺が存在する
            if(color[v] != BLACK && gMatrix[u][v] != INFTY){
                // 2.2最短コストを更新する
                // この処理の終了後weight[v]sからS内の頂点のみを経由したvまでの最短コストが記録される
                if(weight[v] > weight[u] + gMatrix[u][v]){
                    weight[v] = weight[u] + gMatrix[u][v];
                    color[v] = GRAY;
                }
            }
        }
    }
    // 出力
    for(int i = 0;i < n;++i){
        cout << i << " " << ( weight[i] == INFTY ? -1 : weight[i] ) << endl;
    }
}

int main(){
    int n;
    cin >> n;
    
    for(int i = 0;i < n;++i){
        for(int j = 0;j < n;++j){
            gMatrix[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;
            gMatrix[u][v] = c;
        }
    }
    dijkstra(n);
    return 0;
}

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

#define go first
#define ct second

int cost[100 + 10] , cost_ps[100 + 10];
int n,vf,k,v,c;

int v_k[100];

vector< pair<int, int> > went[100];

pair<int, int> p_tmp;

int  check_go(int st)
{
	int i;
	int ret=0;

	for (i = 0; i < v_k[st]; i++)
	{
		if (cost_ps[went[st][i].go] > cost[st] + went[st][i].ct || cost_ps[went[st][i].go] == -1)
		{
			cost_ps[went[st][i].go] = cost[st] + went[st][i].ct;
		}
	}

	for (i = 1; i < n; i++)
	{
		if ( (cost_ps[ret] > cost_ps[i] && cost[i]==-1 && cost_ps[i]!=-1 ) || cost[ret] != -1 )
		{
			cout << "B" << cost[ret] << endl;
			ret = i;
			printf("ret=%d\n", ret);
		}
	}
	cout << cost_ps[ret] << endl;

	cost[ret] = cost_ps[ret];
	cout << "A" << cost[ret] << endl;

	return ret;

}

int main()
{
	int i,j;
	int st_num=0;

	cin >> n;

	for (i = 0; i < n; i++)
	{
		cost[i] = cost_ps[i] = -1;

		cin >> vf ;
		cin >> v_k[vf];
		for (j = 0; j < v_k[vf] ; j++)
		{
			cin >> p_tmp.go >> p_tmp.ct;

			went[vf].push_back(p_tmp);
		}
	}

	cost[0] = cost_ps[0] = 0;

	for (i = 1; i < n; i++)
	{
		st_num = check_go(st_num);
	}

	for (i = 0; i < n; i++)
	{
		cout << i << " " << cost_ps[i] << endl;
	}

	return 0;
}

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

const int N=100;
const int INF=2000000000;
const int WHITE=0;
const int GRAY=1;
const int BLACK=2;

int n,M[N][N],d[N],color[N];

void dijkstra(){
    d[0]=0;
    color[0]=GRAY;
    while(true){
        int min_des=INF;
        int vertex=-1;
        for(int i=0;i<n;i++){
            if(min_des>d[i]&&color[i]==GRAY){
                min_des=d[i];
                vertex=i;
            }
        }
        if(vertex==-1) break;
        color[vertex]=BLACK;
        for(int i=0;i<n;i++){
            if(color[i]!=BLACK&&M[vertex][i]<INF){
                if(d[i]>d[vertex]+M[vertex][i]){
                    d[i]=d[vertex]+M[vertex][i];
                    color[i]=GRAY;
                }
            }
        }
    }
}        

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

    for(int u=0;u<n;u++){
        cout<<u<<' '<<d[u]<<endl;
    }
}