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<iostream>
#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];

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

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();
return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
const int MAX_N = 10000;
const int INF = 999999999;
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
using namespace std;

int n;
vector<pair<int, int> > adj[MAX_N];
int color[MAX_N];
int d[MAX_N];

void dijkstra(int s) {
    priority_queue<pair<int, int> > PQ;
    for (int i = 0; i < n; i++) {
        color[i] = WHITE;
        d[i] = INF;
    }

    d[s] = 0;
    PQ.push(make_pair(0, 0));
    color[s] = GRAY;

    while (!PQ.empty()) {
        pair<int, int> edge = PQ.top(); PQ.pop();
        int u = edge.second;
        color[u] = BLACK;

        if (d[u] < edge.first * (-1)) continue;

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

    }
}

int main(void) {
    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;
            adj[i].push_back(make_pair(v, c));
        }
    }

    dijkstra(0);

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

    return 0;
}

C++: #include<stdio.h>
#include<cmath>
#include<algorithm>
#include<stack>
#include<queue>
#include<vector>

typedef long long int ll;

#define BIG_NUM 2000000000

using namespace std;

struct Node {
    Node(int arg_to, int arg_cost) {
        to = arg_to;
        cost = arg_cost;
    }
    
    bool operator<(const struct Node &arg) const{
        return cost > arg.cost;
    };
    
    int to, cost;
};

int main() {
    int N;
    scanf("%d", &N);
    
    vector<Node> V[N];
    
    int node, num, to, cost, D[N];
    
    for(int loop = 0; loop < N; loop++) {
        scanf("%d", &node);
        scanf("%d", &num);
        
        for(int i = 0; i < num; i++) {
            scanf("%d %d", &to, &cost);
            V[node].push_back(Node(to, cost));
        }
        D[loop] = BIG_NUM;
    }
    
    D[0] = 0;
    
    priority_queue<Node> Q;
    
    for(int i = 0; i < V[0].size(); i++) {
        D[V[0][i].to] = V[0][i].cost;
        Q.push(Node(V[0][i].to, V[0][i].cost));
    }
    
    int min_index;
    
    while(!Q.empty()) {
        if(Q.top().cost == D[Q.top().to]) {
            min_index = Q.top().to;
            Q.pop();
        }else {
            Q.pop();
            continue;
        }
        
        for(int k = 0; k < V[min_index].size(); k++) {
            if(D[V[min_index][k].to] > D[min_index] + V[min_index][k].cost) {
                D[V[min_index][k].to] = D[min_index] + V[min_index][k].cost;
                Q.push(Node(V[min_index][k].to, D[V[min_index][k].to]));
            }
        }
    }
    
    for(int i = 0; i < N; i++) printf("%d %d\n", i, D[i]);
    
    return 0;
}

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

typedef pair<int, int> node;
typedef vector<node> Adj_list;
typedef vector<Adj_list> Adj_lists;

class less_cost{
public:
  bool operator()(const pair<int, int> lhs, const pair<int, int> rhs) const{
    return lhs.second < rhs.second;
  }
};

int main(){

  int n;
  scanf("%d", &n);

  Adj_lists adj_lists(n);

  // read weigts
  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);
      adj_lists.at(u).push_back(node(v, c));
    }
  }

  // initialize cost
  vector<int> d(n, INT_MAX);
  d.at(0) = 0;
  priority_queue<node, vector<node>, less_cost> pq;
  pq.push(node(0, d.at(0)));
  vector<bool> is_belong_to_sssp(n, false);

  //dijkstra's algorithm
  while(!pq.empty()){
    // extract node u in V-S that has minimum cost
    const node u = pq.top();
    pq.pop();
    is_belong_to_sssp.at(u.first) = true;

    // if u's cost is larger than d[u],
    // than ignore this one
    if(u.second < d.at(u.first)) continue;

    // update node in V-S and adjacent to u
    for(const node& v : adj_lists.at(u.first)){
      if(!is_belong_to_sssp.at(v.first) && d.at(u.first) + v.second < d.at(v.first)){
        d.at(v.first) = d.at(u.first) + v.second;
        pq.push(node(v.first, d.at(v.first)));
      }
    }
  }

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

  return 0;
}