Go: package main

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

const NIL = -1

type Node struct {
	id     int
	weight int
}

func init() {
	sc.Split(bufio.ScanWords)
}

type NodeHeap []Node

func (h NodeHeap) Len() int           { return len(h) }
func (h NodeHeap) Less(i, j int) bool { return h[i].weight < h[j].weight }
func (h NodeHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

func (h *NodeHeap) Push(x interface{}) {
	*h = append(*h, x.(Node))
}

func (h *NodeHeap) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}

var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func main() {
	n := scanInt()

	route := make([][]Node, n)
	weight := make([]int, n)
	for i := 0; i < n; i++ {
		weight[i] = NIL
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		route[i] = make([]Node, k)
		for j := 0; j < k; j++ {
			route[u][j] = Node{id: scanInt(), weight: scanInt()}
		}
	}

	start := Node{id: 0, weight: 0}
	h := &NodeHeap{start}
	heap.Init(h)

	for h.Len() > 0 {
		node := heap.Pop(h).(Node)
		if weight[node.id] != NIL {
			continue
		}
		weight[node.id] = node.weight

		for _, nextNode := range route[node.id] {
			if weight[nextNode.id] != NIL {
				continue
			}
			nextNode.weight += node.weight
			heap.Push(h, nextNode)
		}
	}

	for i, w := range weight {
		fmt.Println(i, w)
	}
}

C++: #include <stdio.h>
#include <iostream>
#include <queue>
using namespace std;

#define NIL -1
#define INF 100000000
#define WHITE 1
#define GREY 2
#define BLACK 3
#define N_MAX 100

int G[N_MAX][N_MAX];
int V[N_MAX];
int V_value[N_MAX];

void init(){
    for(int i = 0; i < N_MAX; i++){
        V[i] = WHITE;
        V_value[i] = INF;
    }

    for(int i = 0; i < N_MAX; i++){
        for(int j = 0; j < N_MAX; j++){
            G[i][j] = NIL;
        }
    }
}

int main(void){
    init();
    int n;
    scanf("%d\n", &n);

    for(int i = 0; i < n; i++){
        int u, k;
        scanf("%d %d", &u, &k);
        for(int j = 0; j < k; j++){
            int v, c;
            scanf("%d %d", &v, &c);
            G[u][v] = c;
        }
    }

    priority_queue<pair<int, int>> PQ;

    V[0] = BLACK;
    V_value[0] = 0;
    int new_node = 0;
    
    while(1){
        for(int i = 0; i < n; i++){
            if(G[new_node][i] != NIL && V[i] == WHITE){
                V_value[i] = min(V_value[i], V_value[new_node] + G[new_node][i]);
                PQ.push(make_pair(V_value[i] * (-1), i));
            }
        }

        int min_value;
        int min_index = NIL;
        while(!PQ.empty()){
            pair<int, int> p = PQ.top(); PQ.pop();
            if(p.first * (-1) == V_value[p.second])
                min_value = p.first * (-1);
                min_index = p.second;
                break;
        }

        if(min_index == NIL)
            break;

        new_node = min_index;
        V[new_node] = BLACK;
        V_value[new_node] = min_value;
    }
    
    for(int i = 0; i < n; i++){
        printf("%d %d\n", i, V_value[i]);
    }

    return 0;
}

C++: #include <iostream>
#include <utility>
#include <queue>
#include <limits>

using namespace std;

static const int MAX=10000;
static const int INF=numeric_limits<int>::max();

int n,d[MAX];
vector<pair<int,int> > list[MAX];

void dijkstra(){
  //initialize as min-Heap
  priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > PQ;
  bool visited[n];
  for(int i=0;i<n;i++){
    visited[i]=false;
    d[i]=INF;
  }
  d[0]=0;
  PQ.push(make_pair(0,0));
  while(!PQ.empty()){
    pair<int,int> f=PQ.top(); PQ.pop();
    int u=f.second;
    visited[u]=true;

    //if(d[u]>f.first) continue;

    for(int i=0;i<list[u].size();i++){
      int v=list[u][i].first;
      if(visited[v]==false && d[v]>d[u]+list[u][i].second){
        d[v]=d[u]+list[u][i].second;
        PQ.push(make_pair(d[v],v));
      }
    }
  }
}

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

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
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; }
const ll INF = 1LL << 60;
const int MAX = 1000000010;
const ll MOD = 1000000007;

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[u].push_back(make_pair(v, c));
        }
    }
    vector<int> d(N, MAX);
    vector<bool> checked(N, false);
    priority_queue<pair<int, int>> pq;
    d[0] = 0;
    pq.push(make_pair(0, 0));

    while (!pq.empty()) {
        auto p = pq.top();
        pq.pop();
        int v = p.second;
        
        if (d[v] < p.first * (-1)) continue;
        checked[v] = true;


        for (auto np : G[v]) {
            int nv = np.first;
            if (checked[nv]) continue;

            if (chmin(d[nv], d[v] + np.second)) pq.push(make_pair(d[nv] * (-1), nv));
        }
    }

    for (int v = 0; v < N; v++) {
        cout << v << " " << d[v] << "\n";
    }
    return 0;
}

C++: #include<algorithm>
#include<queue>
using namespace std;
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]; // Adjacency list

void dijkstra(int s) {
    priority_queue<pair<int, int> > PQ;
    int color[n], d[n], p[n];
    for (int i=0; i<n; i++) {
        color[i] = WHITE;
        d[i] = INFTY;
    }
    d[s] = 0;
    PQ.push(make_pair(0, s));
    color[s] = 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; // Not the minimum
        }

        for (int j=0; j<adj[u].size(); j++) {
            int v = adj[u][j].second;
            if (color[v]==BLACK) {
                continue;
            }
            int tmp = d[u] + adj[u][j].first;
            if (tmp < d[v]) {
                d[v] = tmp;
                color[v] = GRAY;
                PQ.push(make_pair(d[v]*(-1), v)); // Descending order
            }
        }
    }

    for (int i=0; i<n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

int main() {
    scanf("%d", &n);
    int u, k, v, c;
    for (int i=0; i<n; i++) {
        scanf("%d %d", &u, &k);
        for (int j=0; j<k; j++) {
            scanf("%d %d", &v, &c);
            adj[u].push_back(make_pair(c, v));
        }
    }
 
    dijkstra(0);
    return 0;
}