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<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<queue>
using namespace std;
const int inf=0x3f3f3f3f;
const int maxn=109;
int map1[maxn][maxn];
int flag[maxn];
int vis[maxn];
int c[maxn];

void spfa(int u,int n){
    queue<int>q;
    memset(flag,0,sizeof(flag));
    memset(c,0,sizeof(c));
    for(int i=0;i<n;i++)
        vis[i]=inf;
    vis[0]=0;c[0]=1,flag[0]=1;
    q.push(0);
    while(!q.empty()){
        int now=q.front();
        q.pop();
        flag[now]=0;
        for(int i=0;i<n;i++){
            if(vis[i]>vis[now]+map1[now][i]){
                vis[i]=vis[now]+map1[now][i];
                if(!flag[i]){
                    flag[i]=1;
                    q.push(i);
                }

            }
        }
    }
}

int main(){
    int n,u,v,w,k;
    while(scanf("%d",&n)!=EOF){
        for(int i=0;i<n;i++)
            for(int j=0;j<n;j++)
                if(i==j)
                    map1[i][j]=0;
                else
                    map1[i][j]=inf;
        for(int i=0;i<n;i++){
            scanf("%d%d",&u,&k);
            for(int j=0;j<k;j++){
                scanf("%d%d",&v,&w);
                if(map1[u][v]>w)
                    map1[u][v]=w;
            }
        }
        spfa(0,n);
        for(int i=0;i<n;i++)
            printf("%d %d\n",i,vis[i]);
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <map>
#include <queue>
#include <algorithm>
#define INF 1<<30
using namespace std;
int main() {
	cin.tie(0);ios::sync_with_stdio(false);
	int V; cin >> V;
	vector<vector<pair<int, int>>> g(V);
	vector<int> dp(V);
	queue<int> q;

	//input
	for (int i = 0; i < V; i++) {
		int u, k; cin >> u >> k;
		for (int j = 0; j < k; j++) {
			int c, v;
			cin >> c >> v;
			g[u].push_back(make_pair(c, v));
		}
	}

	//initialize
	fill(dp.begin(), dp.end(), INF);
	dp[0] = 0;
	q.push(0);

	//Dijkstra
	while (!q.empty()) {
		int k = q.front(); q.pop();
		for (int i = 0; i < g[k].size();i++) {
			int next = g[k][i].first;
			int w = g[k][i].second;
			if (dp[k] + w < dp[next]) {
				dp[next] = dp[k] + w;
				q.push(next);
			}
		}
	}

	//output
	for (int i = 0; i < V;i++) {
		cout << i << " " << dp[i] << endl;
	}
}

C++: #include <cstdio>
#include <algorithm>
#include <queue>
#include <utility>
#include <unordered_map>
#include <vector>

using edge = std::pair<int, int>;
#define N 100

int main(){
    int n;
    std::scanf("%d", &n);
    std::vector<edge> a[N];
    for(int i = 0; i < n; ++i){
        int id;
        int num;
        std::scanf("%d", &id);
        std::scanf("%d", &num);
        for(int j = 0; j < num; ++j){
            edge e;
            std::scanf("%d", &e.second);//id                                                                                                                                                                                        
            std::scanf("%d", &e.first);//weight                                                                                                                                                                                     
            a[id].push_back(e);
        }
    }
    std::priority_queue<edge, std::vector<edge>, std::greater<edge> > que;
    std::unordered_map<int, int> checked;
    checked.insert(std::make_pair(0, 0));
    for(auto &x: a[0]){
        que.push(x);
    }
    while(checked.size() != n){
        while(checked.find(que.top().second) != checked.end()){
            que.pop();
        }
        edge e = que.top();
        que.pop();
        checked.insert(std::make_pair(e.second, e.first));
        for(auto &x: a[e.second]){
            if(checked.find(x.second) == checked.end()){
                x.first += e.first;
                que.push(x);
            }
        }
    }

    for(int i = 0; i < n; ++i){
        auto x = checked.find(i);
        std::printf("%d %d\n", x->first, x->second);
    }

    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 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(){
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;
}