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>
using namespace std;
#include<cstdio>
#include<vector>
#include<utility>
#include<queue>

typedef vector<pair<int, int> > adj;

struct current_cost
{
	int index, cost;
	bool operator < (const current_cost &cur) const
	{
		return cost > cur.cost;
	}
};

current_cost init(int i, int c)
{
	current_cost cur;
	cur.index = i, cur.cost = c;
	return cur;
}

int main()
{
	int i, j, k, n, m, next, cost;
	scanf("%d", &n);
	adj *adlist;
	adlist = new adj [n];

	for(k = 0; k < n; k++){
		scanf("%d %d", &i, &m);
		for(j = 0; j < m; j++){
			scanf("%d %d", &next, &cost);
			adlist[i].push_back(make_pair(next, cost));
		}
	}
	
	int *d;
	d = new int [n];
	d[0] = 0;
	for(i = 1; i < n; i++){
		d[i] = 200000;
	}

	priority_queue<current_cost> C;
	current_cost cur = init(0, 0);
	C.push(cur);

	int size;
	bool *check;
	check = new bool [n];
	for(i = 0; i < n; i++){ check[i] = false; }

	while(!C.empty())
	{
		cur = C.top(); C.pop();
		if(check[cur.index]) continue;
		check[cur.index] = true;
		printf("%d\n", cur.index);

		i = cur.index;
		size = adlist[i].size();
		for(j = 0; j < size; j++){
			k = adlist[i][j].first;
			if(d[i] + adlist[i][j].second < d[k]){
				d[k] = d[i] + adlist[i][j].second;
				C.push(init(k, d[k]));
			}
		}
	};
	for(i = 0; i < n; i++){ printf("%d %d\n", i, d[i]); }

	return 0;
}

C++: #include <bits/stdc++.h>
using ll = long long;
using namespace std;
static const int MAX = 1e4;
static const int INFTY = (1<<20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
//first: 目的点,second: 距離
vector<pair<int,int> > adj[MAX];

void dijkstra(){
  //first: ある点へのマイナス距離, second: ある点
  priority_queue<pair<int,int> > pq;
  //d[i]: 始点からのiへの距離
  int d[MAX],color[MAX];
  for(int i=0;i<n;i++){
    d[i] = INFTY;
    color[i] = WHITE;
  }
  d[0] = 0;
  pq.push(make_pair(0,0));
  while(!pq.empty()){
    pair<int,int> key = pq.top();
    pq.pop();
    int u = key.second;
    color[u] = BLACK;
    if(d[u] < key.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){
        //ここで最初に更新されているから、pqからtopを取り出すだけでOK
        d[v] = d[u] + adj[u][j].second;
        pq.push(make_pair((-1)*d[v],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();
}

C++: #include<bits/stdc++.h>
//#include<iostream>
using namespace std;
//type
typedef long long ll;
#define pii pair<int, int>
#define vi vector<int>
//x * y * 1.0 can cause overflow
//constant
#define inf (int)(1e9+7)
#define mod (ll)(1e9+7)
#define eps 1e-10
//omission
#define eb emplace_back
#define F first
#define S second
#define SZ(x) ((int)(x).size())
#define all(v) v.begin(), v.end()
#define ios cin.tie(0); ios::sync_with_stdio(false)
#define FIX(a) cout << fixed << setprecision(a)
#define mp make_pair
//manip
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(unique(v.begin(), v.end(), v.end());
#define fill(x, y) memset(x, y, sizeof(x))
#define ceil(a, b) a / b + !!(a % b)
template<class T> T power_mod(T a, T b) {return b ? power(a * a % inf, b / 2) * (b % 2 ? a : 1) % inf : 1;}
template<class T> T power(T a, T b) {return b ? power(a * a, b / 2) * (b % 2 ? a : 1) : 1;}
#define LB(v, x) (int)(lower_bound(v.begin(), v.end(), x) - v.begin())
#define UB(v, x) (int)(upper_bound(v.begin(), v.end(), x) - v.begin())
template<typename T> T gcd(T a, T b) {if (b == 0) return a; return gcd(b, a % b);}
template<typename T> T lcm(T a, T b) {return a / gcd(max(a, b), min(a, b)) * b;} //先に割る!!
#define outa(a, n) rep(i_, n) cout << a[i_] << " "; cout << endl
#define out(a) cout << a << endl
#define outv(v) rep(i, SZ(v)) cout << v[i] << " "; cout << endl
//loop
#define rep(i, n) for (int i = 0, i##_len = (n); i < i##_len; ++i)
#define rep3(i, st, n) for (int i = st; i < n; ++i)
//algorithm
//double pointer, l start, how many adds, can be 0 -> init r = l, sum = 0
//bfs, not x, y, i, j
//not !(i % 2), i % 2 == 0
//minimal required terms
//cast caution
//look constraints always
//ctrl + command + e -> 変数一括変更



int main() {
    
    
   
    int n; cin >> n;
    int table[n]; fill_n(table, n, inf); //0からの距離
    table[0] = 0;
    vector<vector<pii> > edge(n);
    rep(i, n) {
        int u, k; cin >> u >> k;
        rep(j, k) {
            int v, c; cin >> v >> c;
            edge[u].eb(v, c);
        }
        
    }
    
    while (1) {
        int update = 0;
        rep(from, n) {
            rep(j, SZ(edge[from])) {
                int to = edge[from][j].F;
                int cost = edge[from][j].S;
                
                if (table[to] > table[from] + cost) {
                    update = 1;
                    table[to] = table[from] + cost;
                }
            }
        }
        if (update == 0) break;
    }
    
    out(0 << " " << 0);
    rep3(i, 1, n) out(i << " " << table[i]);
        
        
    
    
    
}