Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
type Node struct {
	cost int
	done bool
}

type Edge struct {
	to, cost int
}

const INF = 1 << 60

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	nodes := make([]Node, N)
	for i := 0; i < N; i++ {
		nodes[i].cost = INF
	}
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id] = append(E[id], Edge{to, cost})
		}
	}
	nodes[0].cost = 0
	for {
		cur := 0
		minCost := INF
		for i := 0; i < N; i++ {
			n := nodes[i]
			if !n.done && n.cost < minCost {
				cur = i
				minCost = n.cost
			}
		}
		if minCost == INF {
			break
		}
		nodes[cur].done = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+nodes[cur].cost
			if !nodes[to].done && cost < nodes[to].cost {
				nodes[to].cost = cost
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, nodes[i].cost)
	}
	wtr.Flush()
}

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

enum Color{WHITE, GRAY, BLACK};
struct edge{
        int v,c;
        edge(int v, int c): v(v), c(c){}
};

int n;
vector<vector<edge>> a;
int *r;

void shortestPath(){
        int tmpcost[n];
        Color color[n];
        for(int i=0;i<n;i++) tmpcost[i]=INT_MAX;
        for(int i=0;i<n;i++) color[i]=WHITE;
        tmpcost[0] = 0;
        color[0] = GRAY;
        while(1){
                int mincost=INT_MAX, argmin=-1;
                for(int i=0;i<n;i++){
                        if(color[i]!=GRAY) continue;
                        if(mincost>tmpcost[i]){
                                mincost = tmpcost[i];
                                argmin = i;
                        }
                }
                if(argmin==-1) break;
                color[argmin] = BLACK;
                r[argmin] = mincost;

                for(int i=0;i<a[argmin].size();i++){
                        edge e = a[argmin][i];
                        if(color[e.v]==BLACK) continue;
                        color[e.v] = GRAY;
                        tmpcost[e.v] = tmpcost[e.v]<(mincost+e.c)? tmpcost[e.v] : (mincost+e.c);
                }

        }

}
int main(){
        int u,k,v,c;
        cin>>n;
        a = vector<vector<edge>>(n);
        r = new int [n];
        for(int i=0;i<n;i++){
                cin>>u>>k;
                for(int j=0;j<k;j++){
                        cin>>v>>c;
                        a[u].emplace_back(edge(v,c));
                }
        }

        shortestPath();

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

C++: #include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <algorithm>

using namespace std;
const int INF = 100000000;

template<typename ISTREAM>
void readWeightedGraphMatrix(ISTREAM& cin, vector< vector<int> >& weightedGraphMatrix) {
	size_t n;
	cin >> n;
	int u, k, v, c;
	weightedGraphMatrix = vector< vector<int> >(n, vector<int>(n, -1));
	for (size_t i = 0; i != n; ++i) {
		cin >> u >> k;
		for (size_t j = 0; j != k; ++j) {
			cin >> v >> c;
			weightedGraphMatrix.at(u).at(v) = c;
		}
	}
}

void printSPST(const vector< vector<int> >& weightedGraphMatrix) {//ShortestPathSpaningTree
	enum Color {
		WHITE, GRAY, BLACK//白は未訪問でTと隣接していない。
		//グレーはTと隣接状態だが未訪問、黒は訪問済み。木は閉路を持たないグラフなので、全域木の計算では
		//各点は1度だけ訪問されるはず。
	};
	const size_t n = weightedGraphMatrix.size();
	vector<Color> color(n,Color::WHITE);
	vector<int> d(n, INF);
	vector<int> p(n, -1);
	color.front() = Color::GRAY;
	d.front() = 0;
	int currentNode = 0;
	while (true) {
		int min = INF;
		int u;
		//TからV-Tへ接続する辺の重みの中で最小のものを求める。
		//同時に、その辺に接続する辺のT内のノードを求める。
		for (size_t i = 0; i != n; ++i) {
			if (color.at(i) == Color::BLACK || color.at(i) == Color::WHITE) continue;//訪問済みはスキップ
			if (d.at(i) >= min)continue;
			min = d.at(i);//TからV-Tの中のノードiへ向かう辺の重みの最小値を更新
			u = i;
		}

		if (min == INF) {
			//ノード０からアクセス可能なすべての点を訪問済みになったらMST構築完了
			break;
		}

		color.at(u) = Color::BLACK;//訪問

		for (int v = 0; v != n; ++v) {
			if (color.at(v) == Color::BLACK) continue;//訪問済みはスキップ
			if (weightedGraphMatrix.at(u).at(v) < 0 ) continue;//辺がない場合はスキップ
			const int distanceToVThroughCurrentU = d.at(u) + weightedGraphMatrix.at(u).at(v);
			if (distanceToVThroughCurrentU >= d.at(v)) continue;
			d.at(v) = distanceToVThroughCurrentU;
			p.at(v) = u;
			color.at(v) = Color::GRAY;
		}
	}
	for (int i = 0; i != n; ++i) {
		cout << i << " " << d.at(i) << endl;
	}
}

template<typename T>
void execute(T& cin) {
	vector< vector<int> > graphList;
	readWeightedGraphMatrix(cin, graphList);
	printSPST(graphList);
}


int main()
{


	execute(cin);
	

	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 BLACK=2;
static const int GRAY=1;
int n,M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX],color[MAX];
    for(int i=0;i<n;i++){
        d[i]=INFTY;
        color[i]=WHITE;
    }
    d[0]=0;
    color[0]=GRAY;
    while(1){
        minv=INFTY;
        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)break;
        color[u]=BLACK;
        for(int v=0;v<n;v++){
            if(color[v]!=BLACK&&M[u][v]!=INFTY){
                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]==INFTY ? -1:d[i])<<endl;
    }
}


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