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 <cstring> 
#include <algorithm> 
#include <vector> 
#define INF 2000000000 //??¨?????????????????¢????¶??????????????????????????????§????????°???????????¨????????????????????????
             
#define MAX_V 100
     using namespace std;
     int v,u,c,k,vertex;//number of vertices
     int d[MAX_V];
     int ver[100]={};
     int path[100][100]={};
     int path_exist[100][100];
     int min_index;
     bool used[MAX_V];
     int num_used=0,l;
     vector<int> q;
     void dijkstra(int s)
     {
             fill(d,d+v,INF);
             memset(used,false,sizeof(used));//(s,val,end)?????¢?????§s??????end?????§?????¢???????¢???????false??§?????????
             d[s]=0;
             while(q.size()-num_used != 0){
             		while(used[l]==true){
             			l++;
             		}
             		min_index=l;
                     for(int j=0;j<q.size();j++){
                     	if(!used[j]){//???????????¢????????????????¨??????????????????????????????¶
                     		if(d[min_index] > d[j]/*??´??????*/)
                     		min_index=q.at(j);
                     	}
                     }
                        used[min_index]=true;
                        num_used+=1;
                        for(int j=0;j<ver[min_index];j++){//min_index????????°????????????????????????edge????????¨??????????????????????????°
			  d[path_exist[min_index][j]]=min(d[path_exist[min_index][j]], d[min_index] + path[min_index][path_exist[min_index][j]]);/*??´??????*/
                        } 
            }
            return;
    }
    int main(){
        cin>>v;

        for(int i=0; i<v;i++){
        	cin>>u;
        	cin>>k;
        	ver[u]=k;
        	q.push_back(i);
        	for(int j=0;j< k ; j++){
        		cin>>vertex;
        		cin>>c;
        		path[u][vertex]= c;
        		path_exist[u][j]=vertex;

        	}
        }

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