Go: package main

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

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
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 = j
	pq[j].index = i
}

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
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist *[][]int, n int) *[]int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range (*dist)[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return &shortests
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(&dist, n)
	for i, d := range *shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define  all(x) (x).begin(),(x).end()
typedef long long ll;

int n;
vector<vector<pair<int, int>>> g;
const int INF = 1<<30;

void dijkstra(){
    vector<int> d(n), visited(n);
    priority_queue< pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>> > pq;
    rep(i,n) d[i] = INF;

    pq.push(make_pair(0,0));
    d[0] = 0;
    visited[0] = 1;

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

        visited[u] = 1;
        if (d[u] < p.first) continue;

        for(auto pp: g[u]){
            int v = pp.first;
            if (visited[v] == 1) continue;
            if (d[v] > d[u] + pp.second){
                d[v] = d[u] + pp.second;
                pq.push(make_pair(d[v], v));
            }
        }
    }
    rep(i,n){
        printf("%d %d\n", i, d[i]);
    }
}

int main(){
    cin >> n;
    g.resize(n);
    rep(i,n){
        int u, k;
        cin >> u >> k;
        rep(j, k){
            int to, cost;
            cin >> to >> cost;
            g[u].push_back(make_pair(to, cost));
        }
    }
    dijkstra();
}

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;
}