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 <vector>
#include <cassert>

using size_t = std::size_t;

template<class id_type>
class Graph{
public:
  using vertex_type = size_t;
  struct Edge{
    vertex_type to;
    id_type id;
  };

  struct Edge_Pair{
    vertex_type from;
    vertex_type to;
    id_type id;
  };
private:
  std::vector<vertex_type> ver;
  std::vector<Edge_Pair> edges;
  std::vector<std::vector<Edge>> G;
  std::vector<std::vector<Edge>> rG;
public:
  Graph(size_t sz) : ver(sz) , G(sz) , rG(sz){
    for(size_t i = 0;i < ver.size();i++) ver[i] = i;
  }

  const std::vector<vertex_type>& V() const{
    return ver;
  }

  const std::vector<Edge_Pair>& E() const{
    return edges;
  }

  void add_edge(const Edge_Pair& e){
    edges.push_back(e);
    G[e.from].push_back({e.to,e.id});
    rG[e.to].push_back({e.from,e.id});
  }

  void add_edge(vertex_type from,vertex_type to,id_type id){
    add_edge({from,to,id});
  }

  Graph operator+=(const Edge_Pair& e){
    add_edge(e);
    return *this;
  }


  const std::vector<Edge>& delta_p(vertex_type v) const{
    return G[v];
  }

  const std::vector<Edge>& delta_m(vertex_type v) const{
    return rG[v];
  }

  const std::vector<Edge>& operator[](vertex_type v) const{
    return this->delta_p(v);
  }
};

#include <set>
#include <queue>
#include <functional>

template<class dist_type,class id_type>
std::vector<dist_type> dijkstra(const Graph<id_type>& g,std::function<dist_type(id_type)> cost,size_t s,dist_type init,dist_type INF){
    using vt = typename Graph<id_type>::vertex_type;
    using P = std::pair<dist_type,vt>;
    std::vector<dist_type> dist(g.V().size(),INF);
    dist[s] = init;

    std::priority_queue<P,std::vector<P>,std::greater<P>> que;

    que.push({dist[s],s});

    while(!que.empty()){
      vt v = que.top().second;
      dist_type d = que.top().first;
      que.pop();
      if(dist[v] < d) continue;
      for(const auto & e : g.delta_p(v)){
        if(dist[e.to] > dist[v] + cost(e.id)){
          dist[e.to] = dist[v] + cost(e.id);
          que.push({dist[e.to],e.to});
        }
      }
    }

    return dist;
}

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
#define rep(i,s,e) for(int (i) = (s);(i) <= (e);(i)++)
#define all(x) x.begin(),x.end()

int main(){
  int n;
  cin >> n;
  Graph<size_t> g(n);
  vector<i64> cost;
  for(int i = 0;i < n;i++){
    size_t u,t;
    cin >> u >> t;
    for(int j = 0;j < t;j++){
      size_t v;
      i64 c;
      cin >> v >> c;
      g.add_edge(u,v,cost.size());
      cost.push_back(c);
    }
  }

  auto res = dijkstra<i64,size_t>(g,[&](size_t id)->i64{return cost[id];},0UL,0LL,(i64)1e9);
  for(int i = 0;i < n;i++){
    cout << i << " " << res[i] << endl;
  }
}

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

int n;
vector<pair<int, int> > adj[MAX]; // 重み付き有向グラフの隣接リスト表現

void dijkstra() {
    priority_queue<pair<int, int> > PQ;
    int color[MAX];
    int d[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;
        
        // 最小値を取り出し、それが最短でなければ無視
        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
                // priority_queueはデフォルトで大きい値を優先するため-1をかける
                PQ.push(make_pair(d[v]*(-1), v));
                color[v] = GRAY;
            }
        }
    }
    
    for (int i=0; i<n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

int main() {
    int k, u, v, c;
    
    scanf("%d", &n);
    for (int i=0; i<n; i++) {
        scanf("%d %d", &u, &k);
        for (int j=0; j<k; j++) {
            scanf("%d %d", &v, &c);
            adj[u].push_back(make_pair(v, c));
        }
    }
    
    dijkstra();
    
    return 0;
}