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 <algorithm>
#include <queue>
#include <vector>

using namespace std;

const int MAX=10000;
const int INFTY=(1<<21);
const int WHITE=0;
const int GRAY=1;
const int BLACK=2;

vector<pair<int, int>> adj[MAX];
int n;

void dijkstra(){
    priority_queue<pair<int, int>> PQ;
    int color[MAX],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;

        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]==INFTY ? -1:d[i])<<endl;
    }

    return;
}

int main()
{
    cin>>n;
    int k,u,v,c;

    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();

}

C++: #include<iostream>
#include<vector>
#include<queue>
using namespace std;
struct Edge {
    int d, i, j;
    Edge(int d_, int i_, int j_) : d(d_), i(i_), j(j_) {}
    bool operator< (const Edge& right) const{
        return d > right.d;
    }
};
void calc(int t, vector<vector<pair<int, int > > >& G, vector<int>& distance){
    int new_black = t;
    priority_queue<Edge> temp;
    for (int i = 1; i < G.size(); i++) {
        for (int j = 0; j < G[new_black].size(); j++) {
            if (distance[G[new_black][j].first] != -1) continue;
            int dis = G[new_black][j].second + distance[new_black];
            temp.push(Edge(dis, new_black, G[new_black][j].first));
        }
        while (distance[temp.top().j] != -1) temp.pop();
        distance[temp.top().j] = temp.top().d;
        new_black = temp.top().j;
        temp.pop();
    }
}

int main(){
    int n;
    cin >> n;
    vector<vector<pair<int, int> > > G(n);
    for (int i = 0; i < n; i++) {
        int u, k;
        cin >> u >> k;
        G[u].resize(k);
        for (int j = 0; j < k; j++) {
            int v, c;
            cin >> v >> c;
            G[u][j] = make_pair(v, c);
        }
    }

    vector<int> distance(n, -1);
    distance[0] = 0;
    calc(0, G, distance);
    for (int i = 0; i < n; i++) {
        cout << i << " " << distance[i] << endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll INF = 1e16;
const ll mod = 1000000007;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
template<class T> inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template<class T> inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
int ctoi(char c) {
  if (c >= '0' && c <= '9') {
    return c - '0';
  }
  return 0;
}
ll factorial(ll n) {
  if (n == 1) {
    return 1;
  }
  ll ans = factorial(n-1);
  return ans*n;
}
ll gcd(ll a, ll b) {
  if (a < b) {
    ll tmp = a;
    a = b;
    b = tmp;
  }
  ll r = a%b;
  while(r != 0) {
    a = b;
    b = r;
    r = a%b;
  }
  return b;
}
ll lcm(ll a, ll b) {
  return (a/gcd(a, b))*b;
}
bool prime(ll n) {
  if (n == 1) {
    return false;
  } else {
    for (ll i = 2; i <= (ll)pow(n, 0.5); i++) {
      if (n%i == 0) return false;
    }
  }
  return true;
}
ll RepeatSquaring(ll n, ll p, ll m) {
  if (p == 0) return 1;
  if (p%2 == 0) {
    ll t = RepeatSquaring(n, p/2, m);
    return (t*t)%m;
  }
  return (n*RepeatSquaring(n, p-1, m))%m;
}

vector <ll> color(10000, 0);
vector <ll> d(10000, INF);
priority_queue <pair <ll, ll>> pq;
vector <vector <pair <ll, ll>>> m(10000, vector <pair <ll, ll>> ());
ll n;

void dijkstra() {
  d.at(0) = 0;
  pq.push(make_pair(0, 0));
  while (!pq.empty()) {
    pair <ll, ll> u = pq.top();
    pq.pop();
    color.at(u.second) = 2;
    if (d.at(u.second) < u.first*(-1)) continue;
    rep(i, m.at(u.second).size()) {
      pair <ll, ll> v = m.at(u.second).at(i);
      if (color.at(v.first) != 2) {
        if (d.at(u.second)+v.second < d.at(v.first)) {
          d.at(v.first) = d.at(u.second)+v.second;
          color.at(v.first) = 1;
          pq.push(make_pair(d.at(v.first)*(-1), v.first));
        }
      }
    }
  }
}

int main() {
  cin >> n;
  rep(i, n) {
    ll u, k;
    cin >> u >> k;
    rep(j, k) {
      ll v, c;
      cin >> v >> c;
      m.at(u).push_back(make_pair(v, c));
    }
  }
  dijkstra();
  rep(i, n) {
    cout << i << ' ' << d.at(i) << endl;
  }
}