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 <algorithm>
#include <iostream>
#include <queue>
using namespace std;

static const int Max = 100;
static const int Inf = 1000000;
enum State {
	Not_Searched = 0,
	Connected = 1,
	Searched = 2
};

int n = 0;
vector<pair<int, int> > adj[Max]; // pair<??£??\??????index, ??????cost> 

void dijkstra() {
	priority_queue<pair<int, int> > pq; // pair<start ???????????????????????????????????§????????????????´???????idx>
	int st[Max];
	int min_cost[Max];
	for (int i = 0; i < n; i++) {
		st[i] = Not_Searched;
		min_cost[i] = Inf;
	}

	min_cost[0] = 0;
	pq.push(make_pair(0, 0));
	st[0] = Connected;

	while (!pq.empty()) {
		pair<int, int> f = pq.top();
		pq.pop();
		int u = f.second;
		st[u] = Searched;

		if (min_cost[u] < f.first * (-1)) continue;

		for (int i = 0; i < adj[u].size(); i++) {
			int adj_u_idx = adj[u][i].first;
			if (st[adj_u_idx] == Searched) continue;
			if (min_cost[adj_u_idx] > min_cost[u] + adj[u][i].second) {
				min_cost[adj_u_idx] = min_cost[u] + adj[u][i].second;
				pq.push(make_pair(min_cost[adj_u_idx]*(-1), adj_u_idx));
				st[adj_u_idx] = Connected;
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << " " << (min_cost[i] == Inf ? -1 : min_cost[i]) << endl;
	}
	return;
}

int main() {
	cin >> n;
	int u, k, vi, ci;
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> vi >> ci;
			adj[u].push_back(make_pair(vi, ci));
		}
	}

	dijkstra();
	return 0;
}

C++: #include <iostream> 
#include <queue>
#include <algorithm>
#define MAX 1000
#define INF (1<<21)
#define WHITE 0
#define GRAY  1
#define BLACK 2
using namespace std;

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

void Dijkstra() 
{
    priority_queue<pair<int,int>> PQ;
    int next, min_cost;
    int color[n], dist[n];

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

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

    while(! PQ.empty())
    {
        pair<int, int> next = PQ.top(); PQ.pop();
        int u = next.second;

        color[u] = BLACK;

        if (dist[u] < next.first * (-1)) continue;

        for (int i = 0; i < adj_list[u].size(); ++i) 
        {
            int v = adj_list[u][i].first;
            if (color[v] == BLACK) continue;
            if (dist[v] > dist[u] + adj_list[u][i].second)
            {
                color[v] = GRAY;
                dist[v] = dist[u] + adj_list[u][i].second;
                PQ.push(make_pair(dist[v]*(-1), v));
            }
        }
    }
    
    int sum = 0;
    for (int i = 0; i < n; ++i) 
    {
        cout << i << ' ' << (dist[i] != INF ? dist[i] : -1) << endl; 
    }
}

int main() 
{
    int id, deg, v, w;

    cin >> n;
    for (int i = 0; i < n; ++i) 
    {
        cin >> id >> deg;
        for (int j = 0; j < deg; ++j) 
        {
            cin >> v >> w;
            adj_list[id].push_back(make_pair(v, w));
        }
    }

    Dijkstra();

    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<vector>
#include<utility>
#include<limits>
using namespace std;
typedef pair<int, int> Edge;
const int MAX = 1000000000;
int main()
{
	int n; cin >> n;
	vector< vector< Edge > > lists;

	for (int i = 0; i < n; i++)
	{
		vector<Edge> list;
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; j++)
		{
			Edge edge;
			cin >> edge.second >> edge.first;
			list.push_back(edge);
		}
		lists.push_back(list);
	}

	vector<int> costs(n, MAX);
	costs[0] = 0;
	priority_queue<Edge> queue;
	for (Edge edge : lists[0])
		queue.push(edge);

	while (!queue.empty())
	{
		Edge edge = queue.top(); queue.pop();
		int dest = edge.second;
		int cost = edge.first;
		if (costs[dest] < cost)continue;
		int new_cost = costs[edge.second] = edge.first;

		for (Edge next : lists[dest])
		{
			next.first += new_cost;
			queue.push(next);
		}
	}
	for (int i = 0; i < n; i++)
		cout << i << " " << costs[i] << endl;

	char c;
	cin >> c;

	return 0;
}

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

#include<vector>
#include<utility>

using namespace std;

#define MAX 10000
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define INFTY 1<<21

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

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

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

  while( !PQ.empty() ){
    pair<int, int> present = PQ.top();
    PQ.pop();

    int u = present.second;
    color[u] = BLACK;

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

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

}

int main(void){
  cin >> n;
  int u,k;
  int s,t;
  for(int i=0;i<n;i++){
    cin >> u >> k;
    for(int j=0;j<k;j++){
      cin >> s >> t;
      adj[u].push_back(make_pair(s, t));
    }
  }

  dijkstra();

  return 0;
}

C++: #include <vector>
#include <iostream>
#include <algorithm>
#include <limits>

using namespace std;
using graph = vector<vector<int>>;


int main() {
    int n;
    cin >> n;

    graph G(n, vector<int>(n, -1));
    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][v] = c;
        }
    }

    // Dijkstra's algorithm
    vector<int> d(n, -1);
    vector<bool> visited(n, false);

    d[0] = 0;
    visited[0] = true;
    while (1) {
        int u = -1;
        int v = -1;
        int minw = numeric_limits<int>::max();
        for (int i = 0; i < n; ++i) {
            if (!visited[i])
                continue;
            for (int j = 0; j < n; ++j) {
                if (visited[j] || G[i][j] < 0)
                    continue;
                int w = G[i][j] + d[i];
                if (w < minw) {
                    u = i;
                    v = j;
                    minw = w;
                }
            }
        }
        if (v < 0) {
            break;
        }
        d[v] = minw;
        visited[v] = true;
    }

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

    return 0;
}