Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
)

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}
func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = i
	pq[j].index = j
}
func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}
func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 // for safety
	*pq = old[0 : n-1]
	return item
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

C++: //ALDS1_12C
#include <iostream>
#include <algorithm>
#include <queue>
using namespace std;
 
static const int MAX=10000;
static const int INF=(1<<21);
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;
 
int n;
vector<pair<int,int> > adj[MAX];
 
int dijkstra(){
 priority_queue<pair<int,int> > PQ;
 int d[MAX],color[MAX];
 for(int i=0;i<n;i++){
  d[i]=INF;
  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]==INF ? -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;
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <deque>
#include <queue>
#include <list>
#include <stack>
#include <string>
#include <tuple>
#include <functional>
#include <numeric>
#include <cmath>
#include <iomanip>
#include <map>
#include <random>
#include <cstdlib>
#define INT_MAX 2147483647
#define INT_MIN -2147483646
#define Loop(i, n) for(int i = 0; i < (int)n; i++)
#define Loop1(i, n) for(int i = 1; i <= (int)n; i++)
#define Loopr(i, n) for(int i = (int)n - 1; i >= 0; i--)
#define Loopr1(i, n) for(int i = (int)n; i >= 1; i--)
using namespace std;
typedef long long int ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;

static const int N = 10005;

struct vertex {
	int id;
	int d;
	bool operator<(const vertex & another) const {
		return (d != another.d ? d>another.d : id>another.id);
	}
};

struct edge {
	int end;
	int w;
};

int main() {
	int n;
	cin >> n;
	vector<vector<edge>> E(N);
	Loop(i, n) {
		int u, k;
		cin >> u >> k;
		Loop(i, k) {
			int v, c;
			cin >> v >> c;
			E[u].push_back({ v,c });
		}
	}

	priority_queue<vertex> pq;
	vi color(N, 0), dist(N, 0);     //!
	pq.push({ 0,0 });
	int cnt = 0;
	while (pq.size() > 0) {
		if (cnt == n) break;
		vertex v = pq.top();
		pq.pop();
		if (color[v.id] == 1) continue;
		dist[v.id] = v.d;
		color[v.id] = 1;
		cnt++;
		Loop(j, E[v.id].size()) {
			if (color[E[v.id][j].end] != 1) {
				pq.push({ E[v.id][j].end, dist[v.id] + E[v.id][j].w });
			}
		}
	}
	Loop(i, n) {
		cout << i << " " << dist[i] << endl;
	}
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<21);
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++){
        color[i] = WHITE;
        d[i] = INFTY;
    }

    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を掛ける
                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, u, v, c;

    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;
}

C++: #include <iostream>
#include <queue>
#include <algorithm>
#define N 10000
#define INF 1000000000

int n;
std::vector<std::pair<int, int> > adj[N];  //

void dijkstra(){
  std::priority_queue<std::pair<int , int> > PQ;  //Container adapter
  std::vector<int> Set(N, 1); //create int number of N, all value initialization to 1
  std::vector<int> d(N, INF); //create int number of N, all value initialization to INF

  d[0] = 0;
  PQ.push(std::make_pair(0, 0)); //add elements of PQ
  Set[0] = 1;

  while( PQ.empty() != 1 ){
    std::pair<int, int> f = PQ.top(); //Extract elements in priority order
    PQ.pop();//Erase the next element

    int u = f.second;
    Set[u] = 2;

    if( d[u] < f.first*(-1) ) continue;

    //   std::cout << adj[u].size() << std::endl;
    for(int i=0; i<adj[u].size(); i++){
      int v = adj[u][i].first;
      if( Set[v] == 2 )continue;
      if( d[v] > d[u] + adj[u][i].second ){
        d[v] = d[u] +adj[u][i].second;
        PQ.push(std::make_pair(d[v]*(-1), v));
        Set[v] = 1;
      }
    }
  }
  for(int j=0; j<n; j++){
    std::cout << j << " " << (d[j] == INF ? -1 : d[j]) << std::endl;
  }
}

int main(){
  int u, k, v, c;
  //Input
  std::cin >> n;
  for(int i=0; i<n; i++){
    std::cin >> u >> k;
    for(int j=0; j<k; j++){
      std::cin >> v >> c;
      adj[u].push_back(std::make_pair(v, c));
    }
  }
  dijkstra();
  return 0;
}