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>
#define INF 1<<30
using std::cin;
using std::cout;
using std::endl;
typedef struct { int vertex, cost; } pair;
pair pqueue[500000], graph[10000][10001];
int mincost[10000], size;
void fswap(pair *x, pair *y) {
  pair tmp;
  tmp = *x;
  *x = *y;
  *y = tmp;
}
void maxheap(int x) {
  int left = 2 * x, right = 2 * x + 1, minimum = x;
  if (left <= size && pqueue[left].cost<pqueue[x].cost) minimum = left;
  if (right <= size && pqueue[right].cost<pqueue[minimum].cost) minimum = right;
  if (minimum != x) {
    fswap(&pqueue[x], &pqueue[minimum]);
    maxheap(minimum);
  }
}
int extract() {
  while (1) {
    pair x = pqueue[1];
    pqueue[1] = pqueue[size--];
    maxheap(1);
    if (mincost[x.vertex] == INF) {
      mincost[x.vertex] = x.cost;
      return x.vertex;
    }
    if (size <= 0) return INF;
  }
}
void insert(pair x) {
  pqueue[++size] = x;
  int cur = size;
  while (cur != 1 && pqueue[cur].cost<pqueue[cur / 2].cost) {
    fswap(&pqueue[cur], &pqueue[cur / 2]);
    cur /= 2;
  }
}
int main() {
  int n; cin >> n;
  for (int i = 0; i < n; ++i) {
    int u, k; cin >> u >> k;
    for (int j = 0; j < k; ++j) cin >> graph[u][j].vertex >> graph[u][j].cost;
    graph[u][k].cost = INF;
  }
  for (int i = 0; i < n; ++i) mincost[i] = INF;
  insert({ 0,0 });
  while (1) {
    int x = extract();
    if (x == INF) break;
    for (int i = 0; graph[x][i].cost != INF; ++i)
      if(mincost[graph[x][i].vertex]==INF) insert({ graph[x][i].vertex,mincost[x] + graph[x][i].cost });
  }
  for (int i = 0; i < n; ++i) cout << i << " " << mincost[i] << endl;
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define INF 10000000

// O(ElogE)

// pq<pair> はfirstが大きい順に出てくるのですか？
// s:= 開始ノード  v:= 頂点数  adjlist:= 隣接リスト (first:= コスト   second:= 行先)
vector<int> dijk(int s, int v, vector<vector<pair<int, int> > > adjlist){
    
    priority_queue <pair<int, int> > wait;
    vector<int> result(v, INF);

    //スタート地点を追加
    result[s] = 0;
    wait.push(make_pair(0, s));

    //ダイクストラ本体
    while(!wait.empty()){    //waitが空になるまで

        int nowpoint = wait.top().second;
        int nowcost = -wait.top().first;
        wait.pop();

        if(result[nowpoint] < nowcost) continue;


        //今いる頂点と隣接しているすべての頂点をなめる
        for(int i = 0; i < adjlist[nowpoint].size(); i++){

            int nextpoint = adjlist[nowpoint][i].second;
            int nextcost = nowcost + adjlist[nowpoint][i].first;
            //現時点より安く到達できそうであれば、結果を更新して優先度付きキューに格納
            if(result[nextpoint] > nextcost){
                result[nextpoint] = nextcost;
                wait.push(make_pair(-nextcost, nextpoint));
            }
        }
    }
    
    return result;         //結果列を返す
}

int main(){

    int V; cin >> V;
    vector<vector<pair<int, int> > > adjlist(V);      //first := コスト　second := 行先

    //入力
    for(int i = 0; i < V; i++){
        int gomi; cin >> gomi;
        int k; cin >> k;
        for(int j = 0; j < k; j++){
            int v, c; cin >> v >> c;           // a ,b 間に コスト c の辺がある
            adjlist[i].push_back(make_pair(c, v));
        }     
    }

    vector<int> result(V);
    result = dijk(0, V, adjlist);
    //cout << result[G] << endl;

    for(int i = 0; i < V; i++){
        cout << i << " " << result[i] << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
// N 为邻接矩阵的大小
#define N 10001
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define INFTY 1 << 21

using namespace std;

int color[N], d[N], p[N];
vector<pair<int, int> > adj[N];

void dijkstra (int s, int n) {
  priority_queue<pair<int, int> > PQ;

  for (int i = 0; i < n; i++) {
    color[i] = WHITE;
    d[i] = INFTY;
  }

  d[s] = 0;
  p[s] = -1;
  PQ.push(make_pair(0, 0));
  color[0] = GRAY;

  while (PQ.size()) {
    pair<int, int> f = PQ.top();
    PQ.pop();
    int u = f.second;

    color[u] = BLACK;

    // 取出最小值，如果不是最短路径就忽略
    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 && d[u] + adj[u][j].second < d[v]) {
        d[v] = d[u] + adj[u][j].second;
        p[v] = u;
        // 优先队列默认优先较大值，因此要乘以 -1
        PQ.push(make_pair(d[v] * (-1), v));
        color[v] = GRAY;
      }
    }
  }
}

int main () {
  int n, u, v, degree, cost;
  
  cin >> n;

  for (int i = 0; i < n; i++) {
    cin >> u >> degree;
    
    for (int j = 0; j < degree; j++) {
      cin >> v >> cost;
      
      adj[i].push_back(make_pair(v, cost));
    }
  }

  dijkstra(0, n);

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

  return 0;
}