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 <climits>
#include <iostream>
#include <utility>
#include <vector>

using namespace std;

void dijkstra(vector<vector<pair<int, int>>>& g, vector<int>& weights) {
    int n_vertex = weights.size();
    vector<bool> visited(n_vertex, false);
    weights[0] = 0;
    while (true) {
        int min_idx;
        int min_weight = INT_MAX;
        for (int i = 0; i < n_vertex; ++i) {
            if (!visited[i] && weights[i] < min_weight) {
                min_idx = i;
                min_weight = weights[i];
            }
        }

        if (min_weight == INT_MAX)
            break;

        visited[min_idx] = true;

        for (int i = 0; i < g[min_idx].size(); ++i) {
            int adj = g[min_idx][i].first;
            int weight_via_idx = weights[min_idx] + g[min_idx][i].second;
            if (!visited[adj] && weight_via_idx < weights[adj]) {
                weights[adj] = weight_via_idx;
            }
        }
    }
}

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;
        for (int j = 0; j < k; ++j) {
            int v, c;
            cin >> v >> c;
            g[i].push_back(make_pair(v, c));
        }
    }

    vector<int> weights(n, INT_MAX);
    dijkstra(g, weights);
    for (int i = 0; i < n; ++i)
        cout << i << ' ' << weights[i] << '\n';
}

C++: #include <bits/stdc++.h>
using namespace std;
#define MAX 100
#define INFTY (1<<21)
#define WHITE 0
#define GRAY 1
#define BLACK 2

int n, M[MAX][MAX];

void dijkstra() {
  int minv;
  int d[MAX], color[MAX];

  for ( int i = 0; i < n; i ++) {
    d[i] = INFTY;
    color[i] = WHITE;
  }

  d[0] = 0;
  color[0] = GRAY;
  while ( 1 ) {
    minv = INFTY;
    int u = -1;
    for ( int i = 0; i < n; i++) {
      if (minv > d[i] && color[i] != BLACK) {
        u = i;
        minv = d[i];
      }
    }
    if ( u == -1 ) break;
    color[u] = BLACK;
    for (int v = 0; v < n; v++) {
      if (color[v] != BLACK && M[u][v] != INFTY) {
        if (d[v]> d[u] + M[u][v]) {
          d[v] = d[u] + M[u][v];
          color[v] = GRAY;
        }
      }
    }
  }
  for (int i =0; i< n; i++) {
    cout << i << " " << ( d[i] == INFTY ? -1 : d[i]) << endl;
  }
}

int main(){
	cin >> n;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      M[i][j] = INFTY;
    }
  }
  int k, c, u, v;
  for (int i = 0; i < n; i++) {
    cin >> u >> k;
    for (int j = 0; j<k;j++) {
      cin >> v >> c;
      M[u][v] = c;
    }
  }
  dijkstra();

  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

using ll = long long int;
using P = pair<int,int>;
constexpr int INF = 1<<30;

int n;
vector<vector<P> > g;
vector<int> d;

void dijkstra(int s){
    fill(d.begin(), d.end(), INF);
    d[s] = 0;
    priority_queue<P, vector<P>, greater<P> > que;
    que.push(make_pair(d[s],s));

    while(!que.empty()){
        P p = que.top();
        que.pop();
        int v = p.second;
        if(d[v] < p.first) continue;
        int k = int(g[v].size());
        for(int i=0;i<k;i++){
            int u = g[v][i].first, c = g[v][i].second;
            if(d[u] > d[v] + c){
                d[u] = d[v] + c;
                que.push(make_pair(d[u], u));
            }
        }
    }
}

int main(){
    cin >> n;
    g.resize(n);
    d.resize(n);
    for(int i=0;i<n;i++){
        int v, k;
        cin >> v >> k;
        for(int j=0;j<k;j++){
            int u, c;
            cin >> u >> c;
            g[v].push_back(make_pair(u,c));
        }
    }
    dijkstra(0);
    for(int i=0;i<n;i++){
        cout << i << " " << d[i] << endl;
    }
    return 0;
}

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

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

void dijkstra(){
    priority_queue<pair<int, int> > PQ;
    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));
    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;
}
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;
}