Go: package main

import (
	"bufio"
	"container/heap"
	"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
const INF = 1 << 60

type Edge struct {
	to, cost int
}

type Node struct {
	id, cost int
}

type PQ []Node

func (pq PQ) Len() int           { return len(pq) }
func (pq PQ) Less(i, j int) bool { return pq[i].cost < pq[j].cost }
func (pq PQ) Swap(i, j int)      { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PQ) Push(x interface{}) {
	*pq = append(*pq, x.(Node))
}

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

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		E[id] = make([]Edge, k)
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id][j] = Edge{to, cost}
		}
	}

	d := make([]int, N)
	for i := 0; i < N; i++ {
		d[i] = INF
	}
	done := make([]bool, N)
	pq := &PQ{}
	heap.Init(pq)
	d[0] = 0
	heap.Push(pq, Node{0, 0})
	for pq.Len() > 0 {
		cur := heap.Pop(pq).(Node).id
		if done[cur] {
			continue
		}
		done[cur] = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+d[cur]
			if !done[to] && cost < d[to] {
				d[to] = cost
				heap.Push(pq, Node{to, cost})
			}
		}
	}

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

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

enum Color{WHITE, GRAY, BLACK};
struct edge{
        int v,c;
        edge(int v, int c): v(v), c(c){}
};
bool operator< (const edge &e, const edge &f){return e.c<f.c;}

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

void dijkstra(){
        Color color[n];
        for(int i=0;i<n;i++) color[i]=WHITE;
        color[0] = GRAY;
        priority_queue<edge> pq;
        pq.push(edge(0,0));
        while(!pq.empty()){
                edge e = pq.top(); pq.pop();
                if(color[e.v]==BLACK) continue;
                color[e.v] = BLACK;
                r[e.v] = - e.c;

                for(int i=0;i<a[e.v].size();i++){
                        edge f = a[e.v][i];
                        if(color[f.v]==BLACK) continue;
                        color[f.v] = GRAY;
                        int cost = e.c - f.c;
                        pq.push(edge(f.v, cost));
                }
        }

}

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));
                }
        }

        dijkstra();

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

C++: #include<bits/stdc++.h>
using namespace std;
inline int in()
{
    char c=getchar();
    while(!isdigit(c))c=getchar();
    int x=0;
    while(isdigit(c))
    {
        x=x*10+c-'0';
        c=getchar();
    }
    return x;
}

typedef pair<int,int>pii; //<distance,point>
const int MAX=10000+5;
struct edge
{
    int v;
    int w;
};
vector<edge>e[MAX];
int dis[MAX];
void dijkstra(const int p)
{
    memset(dis,0x3f,sizeof(dis));
    dis[p]=0;
    priority_queue<pii,vector<pii>,greater<pii> >q;
    q.push(make_pair(0,p));
    while(!q.empty())
    {
        pii P=q.top();
        q.pop();
        const int now=P.second;
        if(dis[now]<P.first)continue;
        const int len=e[now].size();
        for(int i=0;i<len;i++)
        {
             edge const * const j=&e[now][i];
            if(dis[j->v]>dis[now]+j->w)
            {
                dis[j->v]=dis[now]+j->w;
                q.push(make_pair(dis[j->v],j->v));
            }
        }
    }
}
int main()
{
    int n=in();
    for(int i=0;i<n;i++)
    {
        const int u=in(),k=in();
        for(int j=0;j<k;j++)
        {
            edge E;
            E.v=in();E.w=in();
            e[u].push_back(E);
        }
    }
    dijkstra(0);
    for(int i=0;i<n;i++)printf("%d %d\n",i,dis[i]);
}

C++: #include <iostream>
#include <cstdlib>
#include <string>
#include <typeinfo>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <stack>
#include <queue>
using namespace std;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;
static const int INFTY = (1<<20);
static const int MAX =10000;

int n;
vector<pair<int, int> > adj[MAX];

void dijkstra(){
    priority_queue<pair<int, int> > PQ;
    int d[MAX], color[MAX];
    
    for(int i = 0; i < n; i++){
        d[i] = INFTY;
        color[i] = WHITE;
    }
    d[0] = 0;
    PQ.push(make_pair(0,0));
    color[0] = GRAY;
    while(!PQ.empty() ){
        pair<int, int> f = PQ.top();PQ.pop();
        int u = f.second;
        color[u] = BLACK;
        
        if(d[u] < f.first * (-1))continue;
        
        for(int j = 0; j < adj[u].size(); j++){
            int v = adj[u][j].first;
            if(color[v] == BLACK)continue;
            if(d[v] > d[u] + adj[u][j].second){
                d[v] = d[u] + adj[u][j].second;
                PQ.push(make_pair(d[v] * (-1),v));
                color[v] = GRAY;
            }
        }
    }
    for(int i = 0; i < n; i++)cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
}
int main(){
    int k,c,u,v;
    cin >> n;
    for(int i = 0; i < n; i++){
        cin >> u >> k;
        for(int j = 0; j < k; j++){
            cin >> v >> c;
            adj[u].push_back(make_pair(v,c));
        }
    }
    dijkstra();
    return 0;
}