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 <bits/stdc++.h>
using namespace std;

struct Edge
{
        int to, cost;
        Edge () {}
        Edge ( int to, int cost ) : to(to), cost(cost) {}
};

struct Node
{
        int node, cost;
        Node () {}
        Node ( int node, int cost ) : node(node), cost(cost) {}
        bool operator < (const Node &d) const { return ( cost < d.cost ); }
        bool operator > (const Node &d) const { return ( cost > d.cost ); }
};

constexpr int INF = (1 << 30) - 1;
int n;
vector < Edge > G[100005];
int d[10005];

void Dijkstra()
{
        priority_queue < Node , vector < Node > , greater < Node > > pq;

        fill_n(d, 10005, INF);
        d[0] = 0;
        pq.emplace(0, 0);
        
        while ( !pq.empty() ) {
                Node u = pq.top(); pq.pop();
                for ( auto &x : G[u.node] ) {
                        int cost = u.cost + x.cost;
                        if ( d[x.to] > cost ) {
                                d[x.to] = cost;
                                pq.emplace(x.to, cost);
                        }
                }
        }
}

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;
                        G[u].emplace_back(v, c);
                }
        }
        Dijkstra();
        for ( int i = 0; i < n; i++ ) {
                cout << i << " " << d[i] << endl;
        }

        return (0);
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1 << 21);
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 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;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
using namespace std;
#define MAX 10000
#define INFTY (1<<20)
#define WHITE 0
#define GRAY 1
#define 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] << 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>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY =1;
static const int 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;
}