Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

const NIL = -1

type Node struct {
	id     int
	weight int
}

func init() {
	sc.Split(bufio.ScanWords)
}

type NodeHeap []Node

func (h NodeHeap) Len() int           { return len(h) }
func (h NodeHeap) Less(i, j int) bool { return h[i].weight < h[j].weight }
func (h NodeHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

func (h *NodeHeap) Push(x interface{}) {
	*h = append(*h, x.(Node))
}

func (h *NodeHeap) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}

var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func main() {
	n := scanInt()

	list := make([][]int, n)
	weight := make([]int, n)
	for i := range list {
		list[i] = make([]int, n)
		weight[i] = NIL
		for j := range list[i] {
			list[i][j] = NIL
		}
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		for j := 0; j < k; j++ {
			v := scanInt()
			w := scanInt()
			list[u][v] = w
		}
	}

	start := Node{id: 0, weight: 0}
	h := &NodeHeap{start}
	heap.Init(h)

	for h.Len() > 0 {
		node := heap.Pop(h).(Node)
		if weight[node.id] != NIL {
			continue
		}
		weight[node.id] = node.weight

		for i, w := range list[node.id] {
			if w == NIL {
				continue
			}
			heap.Push(h, Node{id: i, weight: w + node.weight})
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		fmt.Fprint(w, i)
		fmt.Fprint(w, " ")
		fmt.Fprint(w, weight[i])
		fmt.Fprintln(w)
	}
	w.Flush()
}

C++: #include <bits/stdc++.h>

#define NIL -2
#define INF 1000000001

using namespace std;
static const int BLK = 2;
static const int GRY = 1;
static const int WHT = 0;

void dijkstra(  const   vector<vector<int> > &weight_matrix, 
                        vector<int> &color,
                        vector<int> &minpath,
                        vector<int> &parent)
{
    int n = (int)weight_matrix.size();
    int u,v;
    int mincost;
    while(true){
        mincost = INF;
        for(int i = 0;i < n;i++){
            if(color[i] != BLK && minpath[i] < mincost){
                mincost = minpath[i];
                u = i;
            }
        }
        if(mincost == INF) break;
        color[u] = BLK;

        for(int v = 0; v < n;v++){
            if(color[v] != BLK && weight_matrix[u][v] < INF){
                if( minpath[v] > minpath[u] + weight_matrix[u][v]){
                    minpath[v] = minpath[u] + weight_matrix[u][v];
                    parent[v] = u;
                    color[v] = GRY;
                }
            }
            
        }
    }
    

}

int main(){
    int mat_size;
    int node, deg;
    int to,weight;
    int temp;
    int cost = 0;

    scanf("%d",&mat_size);
    vector<vector<int> > weight_matrix(mat_size,vector<int>(mat_size,INF));
    vector<int> color(mat_size,WHT);
    vector<int> minpath(mat_size,INF);
    vector<int> parent(mat_size,-1);

    for(int i = 0;i < mat_size;i++){
        scanf("%d %d",&node,&deg);
        for(int j = 0;j < deg;j++){
            scanf("%d %d", &to, &weight);
            weight_matrix[node][to] = weight;
        }
    }
    minpath[0] = 0;
    dijkstra(weight_matrix,color,minpath,parent);
    for(int i = 0; i < mat_size;i++){
        printf("%d %d\n",i,minpath[i]);
    }

    return 0;   
}

C++: #define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <iostream>
#include <list>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <queue>
#include <iomanip>
#define INF 1050000000
 
using namespace std;

#define MAX_V 101

int d[MAX_V][MAX_V];  // d[u][v]は辺e=(u,v)のコスト(存在しない場合はINF、ただしd[i][i]=0とする)
int V;                // 頂点数
void warshall_floyd(int n) {
	V = n;

	//for (int i = 0; i < V; i++)
		for (int j = 0; j < V; j++) 
			for (int k = 0; k < V; k++)
				d[0][j] = min(d[0][j], d[0][k] + d[k][j]);
}

int main(void)
{
	int n, u, v, k, c;

	cin >> n;

	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			if (i == j) d[i][j] = 0; 
			else d[i][j] = INF;
		}
	}

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

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


	return (0);
}

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>

#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define repi(i,a,b) for(int i = (a); i < (b); i++)

using namespace std;

typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;

const int INF=1<<29;
const double EPS=1e-9;

const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};
int V;
int cost[120][120];
int d[120];
bool visit[120];
void dijkstra(int s){
	d[s]=0;
	while(true){
		int v =-1;
		for(int u = 0;u < V;u++){
			if(!visit[u]&&(v==-1||d[u] < d[v])){
				v = u;
			}
		}
		if(v==-1)break;
		visit[v]=true;
		for(int u = 0;u < V;u++){
			d[u] =min(d[u],d[v]+cost[v][u]);
		}
	}
}

int main(){
	cin>>V;
	for(int i =0;i <120;i++){
		d[i]=INF;
		visit[i]=false;
		for(int j =0;j <120;j++){
			cost[i][j]=INF;

		}
	}
	for(int i =0;i < V;i++){
		int u,k;
		cin>>u>>k;
		for(int j =0;j <k;j++){
			int v,c;
			cin>>v>>c;
			cost[u][v]=c;
		}
	}
	dijkstra(0);
	for(int i =0;i <V;i++){
		cout <<i<<" "<<d[i]<<endl;
	}
	return 0;
}

C++: #include <iostream>

using namespace std;
static const int MAX=100;
static const int INFTY= (1<<21);
int M[MAX][MAX]; //?????\??????
int d[MAX]; //?????????????????¬
bool visited[MAX]; //???????¢??????????

void dijkstra(int n)
{
    int min;
    //init
    for(int i=0;i<n;i++)
    {
        visited[i]=false;
        d[i]=INFTY;
    }
    //select node 0
    d[0]=0;
    while(true)
    {
        min=INFTY;
        int min_point=-1;
        for(int i=0;i<n;i++)  //?????????????????????????????\??¶???
        {
            if(min>d[i]&&visited[i]==false)
            {
                min_point=i;
                min=d[i];
            }
        }
        if(min_point==-1) break;  //??????????????°????????????????????????

        visited[min_point]=true;
        //update
        for(int i=0;i<n;i++)
        {
            if(visited[i]==false&&M[min_point][i]!=INFTY)
                if(d[min_point]+M[min_point][i]<d[i])
                    d[i]=d[min_point]+M[min_point][i];
        }
    }
    //print
    for(int i=0;i<n;i++)
        cout<<i<<' '<<(d[i]==INFTY?-1:d[i])<<endl;
}
int main()
{
    int n;
    cin>>n;
    //init
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++)
            M[i][j]=INFTY;
    for(int i=0;i<n;i++)
    {
        int j;
        cin>>j;
        int nodes_num;
        cin>>nodes_num;
        for(int k=0;k<nodes_num;k++)
        {
            int v,d;
            cin>>v>>d;
            M[j][v]=d;
        }
    }
    dijkstra(n);
}