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<iostream>
#include<vector>
#include<queue>
#define INF 2e9
using namespace std;

void Dikstra(const vector<vector<pair<int, int> > >& G, vector<int>& d){
    d[0] = 0;
    priority_queue<pair<int, int> , vector<pair<int, int> >, greater<pair<int, int> > > PQ;
    PQ.push(make_pair(0, 0));
    vector<bool> is_black(d.size(), false);
    is_black[0] = true;
    while (!PQ.empty()) {
        int t = PQ.top().second;
        PQ.pop();
        is_black[t] = true;
        for (int i = 0; i < G[t].size(); i++) {
            int v = G[t][i].first;
            int w = G[t][i].second;
            if (!is_black[v] && d[t] + w < d[v]) {
                d[v] = d[t] + w;
                PQ.push(make_pair(d[v], v));
            }
        }
    }
}

int main(){
    int n;
    cin >> n;
    vector<vector<pair<int, int> > > G(n);
    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;
            G[u].push_back(make_pair(v, c));
        }
    }
    vector<int> d(n, INF);
    Dikstra(G, d);
    for (int i = 0; i < n; 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);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(int s) {
    int color[n], d[n], p[n];
    for (int i=0; i<n; i++) {
        color[i] = WHITE;
        d[i] = INFTY;
    }
    d[s] = 0;
    color[s] = GRAY;

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

        if (mincost == INFTY) {
            break; // All nodes visited
        }

        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++) {
        cout << i << " " << 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 u, k, v, c;
    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(0);
    return 0;
}

C++: #include <iostream>

using namespace std;
#define MAX 100
#define NIL (1<<21)
#define WHITE 0
#define GRAY 1
#define BLACK 2
int G[MAX][MAX];//图的邻接矩阵
int color[MAX];//节点状态
int n;
int d[MAX];//最小权值
int p[MAX];//父亲节点
void dijkstra(){
    for(int i=0;i<n;i++){
        color[i] = WHITE;
        d[i] = NIL;
        p[i] = -1;
    }
    d[0] = 0;
    while(1){
        int u;
        int mincost = NIL;
        for(int i=0;i<n;i++){//循环找到下一个要加入到S中的(d[u]最小值)
            if(color[i]!=BLACK&&d[i]<mincost){
                mincost = d[i];
                u = i;
            }
        }
        if(mincost==NIL){
            break;
        }
        color[u] = BLACK;
        for(int v=0;v<n;v++){//给相邻顶点的d赋值（与之前的相比较，找到最小的）
            if(color[v]!=BLACK&&G[u][v]!=-1){
                    if(d[u]+G[u][v]<d[v]){
                        d[v] = d[u]+G[u][v];
                        p[v] = u;
                    }
                }
            }
        }



}
int main()
{
    cin>>n;
     for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            G[i][j] = -1;
        }

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

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