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 <bits/stdc++.h>
using namespace std;
#define MAX_N 10000

typedef pair<long, long> P;

long N, d[MAX_N];
vector<P> edge[MAX_N];

void dijkstra(){
    bool seen[N];
    fill(seen, seen + N, false);
    priority_queue<P, vector<P>, greater<P> > todo;
    todo.push(P(0, 0));
    
    while(!todo.empty()){
        long dist = todo.top().first, v = todo.top().second;
        todo.pop();
        if(seen[v]) continue;
        d[v] = dist;
        seen[v] = true;
        for(long i = 0; i < edge[v].size(); i++){
            long w = edge[v][i].second, u = edge[v][i].first;
            if(d[v] + w < d[u]){
                d[u] = d[v] + w;
                todo.push(P(d[u], u));
            }
        }
    }
}

int main(){
    cin >> N;
    fill(d, d + MAX_N, LONG_MAX);
    for(long i = 0; i < N; i++){
        long v, k, u, c;
        cin >> v >> k;
        for(long j = 0; j < k; j++){
            cin >> u >> c;
            edge[v].push_back(P(u, c));
        }
    }
    
    dijkstra();
    
    for(long i = 0; i < N; i++)
        cout << i << " " << d[i] << endl;
    
    return 0;
}

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

int INF;
int n;
vector<pair<int, int>> es[10000];

// sから各頂点への最短経路を求める
void dijkstra () {
  
  priority_queue<pair<int, int>> pq;
  int d[10000];

  // 0:未調査 1:調査中 2:調査完了
  int status[10000];

  for (int i = 0; i < n; i++) {
    d[i] = INF;
    status[i] = 0;
  }

  d[0] = 0;
  status[0] = 1;
  pq.push(make_pair(0,0));

  while (!pq.empty()) {

    pair<int, int> p = pq.top(); pq.pop();
    int u = p.second;
    status[u] = 2;

    // 最小値を取り出し、それが最短でなければ無視
    if (d[u] < p.first * (-1)) {
      continue;
    }
    
    for (int i = 0; i < es[u].size(); i++) {
      int v = es[u][i].first;
      if (status[v] == 2) {
        continue;
      }
      if (d[u] + es[u][i].second < d[v]) {
        d[v] = d[u] + es[u][i].second;
        // priority_queueはデフォルトで大きい順を優先するため-1を掛ける
        pq.push(make_pair(d[v] * (-1), v));
        status[v] = 1;
      }
    }
    
  }
  for (int i = 0; i < n; i++) {
    if (d[i] == INF) {
      cout << i << " -1" << endl;
    } else {
      cout << i << " " << d[i] << endl;
    } 
  }
}

int main() {
  
  cin >> n;

  INF = 20000000;

  // 入力を受け取る
  for (int i = 0; i < n; i++) {
    int u, k;
    cin >> u >> k;
    for (int j = 0; j < k; j++) {
      int v, c;
      cin >> v >> c;
      es[u].push_back(make_pair(v,c));
    }
  }

  // ダイクストラ法開始
  dijkstra();

  return 0;
}

C++: #include <algorithm>
#include <iostream>
#include <queue>
#include <vector>
using namespace std;
static const int NMAX = 10000;
#define INF (1 << 30)

int main() {
  int n;
  cin >> n;
  vector<pair<int, int>> adj[NMAX];

  for (int i = 0; i < n; i++) {
    int id, nn;
    cin >> id >> nn;
    for (int j = 0; j < nn; j++) {
      int to, weight;
      cin >> to >> weight;
      // use negative weights for priority_queue
      adj[id].push_back(make_pair(-weight, to));
    }
  }

  bool visited[n];
  int dist[n];
  for (int i = 0; i < n; i++) {
    visited[i] = false;
    dist[i] = -INF;
  }

  priority_queue<pair<int, int>> distQ;

  // add node 0
  for (int i = 0; i < adj[0].size(); i++) {
    distQ.push(adj[0][i]);
    int weight = adj[0][i].first;
    int id = adj[0][i].second;
    dist[id] = weight;
  }
  visited[0] = true;

  while (!distQ.empty()) {
    // find nearest node
    int minnode = distQ.top().second;
    distQ.pop();

    // add node
    visited[minnode] = true;

    // update dist
    for (int i = 0; i < adj[minnode].size(); i++) {
      int weight = adj[minnode][i].first;
      int id = adj[minnode][i].second;

      if (visited[id] == false) {
        int newWeight = dist[minnode] + weight;
        if (-newWeight < -dist[id]) {
          distQ.push(make_pair(newWeight, id));
          dist[id] = newWeight;
        }
      }
    }
  }

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