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++: #include <iostream>
#include <vector>
#include <queue>

using namespace std;

struct Edge{
    int v, c;

    Edge(int v, int c):v(v), c(c){}

//    bool operator >(Edge &e){
//        return c > e.c;
//    }
};

struct SDto{
    int v, d, from;
    SDto(int v, int d, int from): v(v), d(d), from(from){}

//    bool operator <(SDto &that){
//        return d < that.d;
//    }

    friend bool operator>(SDto s1, SDto s2){
        return s1.d > s2.d;
    }

//    friend bool operator<(SDto s1, SDto s2){
//        return s1.d < s2.d;
//    }
};

// dijkstra
const int MAX_N = 10000, INF = 1 << 28;
int distTo[MAX_N];
int parentOf[MAX_N];
void dijkstra(vector<Edge> G[]);

int main() {
//    SDto s1(1, 1, 1);
//    SDto s2(1, 2, 1);
//    cout << (s1 > s2);

    int n;
    cin >> n;

    // Graph
    vector<Edge> G[n];
    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;
            G[u].emplace_back(v, c);
        }
    }

    dijkstra(G);

    for (int l = 0; l < n; ++l) {
        cout << l << " " << distTo[l] << endl;
    }

    return 0;
}

void dijkstra(vector<Edge> G[]){
    fill(distTo, distTo + sizeof(distTo) / sizeof(*distTo), INF);

    priority_queue<SDto, vector<SDto>, greater<SDto>> pq;

    pq.push(SDto(0, 0, -1));
    while(!pq.empty()) {
        SDto sd = pq.top(); pq.pop();
        if (sd.d < distTo[sd.v]) {
            distTo[sd.v] = sd.d;
            for (auto e: G[sd.v]) {
                if (distTo[e.v] < INF) continue;
                pq.push(SDto(e.v, distTo[sd.v] + e.c, sd.v));
            }
        }
    }
}

C++: #include<cstdio>
#include<queue>
#include<algorithm>
#include<vector>
#include<map>
using namespace std;
const int MAX= 100005 ;
const int INF= 1<<30 ;
int n,d[MAX],vis[MAX];
vector<pair<int,int> > G[MAX];
void init(){
	for(int i=0;i<n;i++){
		d[i]=INF;
		vis[i]=0;
	}
	d[0]=0;
}
void dijkstra(){
	priority_queue<pair<int,int> > PQ;
	PQ.push(make_pair(0,0));
	while(!PQ.empty()){
		pair<int,int> f=PQ.top();PQ.pop();
		int u=f.second;
		vis[u]=1;
		if(d[u]>=-f.first){
			for(int i=0;i<G[u].size();i++){
				int v=G[u][i].first;
				if(!vis[v] && d[v]>G[u][i].second+d[u]){
					d[v]=G[u][i].second+d[u];
					PQ.push(make_pair(-d[v],v));
				}
			}
		}
	}
}
int main(){
	int u,k,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);
			G[u].push_back(make_pair(v,c));
		}
	}
	init();
	dijkstra();
	for(int i=0;i<n;i++){
		printf("%d %d\n",i,d[i]);
	}
	return 0;
}

C++: #include <bits/stdc++.h>
#define REP(i,n) for (int i = 0; i <(n); ++i)
#define ALL(v) v.begin(), v.end()
using namespace std;
using ll = long long;
using P = pair<int,int>;

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];
//グラフの隣接リスト表現(重み付き有向)　first:隣接頂点，second; コスト

void dijkstra(){
  priority_queue<pair<int, int>> PQ;  //各隣接頂点の始点からのコストのキュー
  int color[MAX]; //訪問状況
  int d[MAX];     //始点から各頂点までの最小コスト
  //初期化
  for(int i = 0; i < n; ++i){
    d[i] = INFTY;
    color[i]  = WHITE;
  }

  //始点のコストｄ[0]と，，priority_quwueに代入
  d[0] = 0;
  PQ.push(make_pair(0, 0));
  color[0] = GRAY;


  //最短経路の探索ループ

  while( !PQ.empty() ){
     //最小コストの頂点を取得し，確定
    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; //確定した頂点は飛ばす

      //最小コストを比較して，　更新
      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));
        //priority_queueは大きい値を優先するため，−１をかける．
        color[v] = GRAY;
      }
    }
  }

  for( int i = 0; i < n; i++ ){
    cout << i << " "  << (d[i] == INFTY ? -1 : d[i]) << endl;
  }


}

int main(){
  //Input
  int k, u, v, c; //頂点uに隣接する頂点の数， 頂点, 頂点ｋに隣接する頂点, u>vのコスト
  cin >> n;

  REP(i,n){
    cin >> u >> k;
    REP(j,k){
      cin >> v >> c;
      adj[u].push_back(make_pair(v, c));
    }
  }

  //
  dijkstra();

  return 0;
}