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 <cstdio>
#include <vector>
#include <queue>
#include <utility>
#include <limits.h>

#define DIRECTED true //有向か無向か
#define ull unsigned long long
#define mp(X , Y) make_pair(X , Y)

using namespace std;

bool operator>(const pair<ull,int> a, const pair<ull,int> b){
    return a.first > b.first;
}

class dijkstra{
public:
    int num;
    vector<ull> dist;
    vector<int> prev;

    vector<vector<pair<int,ull>>> side; 

    dijkstra(){
    }

    dijkstra(int n){

        num = n;
        //0オリジンとの混合を避けるため+1する
        for(int i = 0; i < n + 1; i++){
            dist.push_back(ULONG_LONG_MAX);
            prev.push_back(-1);
            vector<pair<int,ull>> v;
            side.push_back(v);
        }
    }

    void reset(){
        dist.clear();
        prev.clear();

        for(int i = 0; i < num + 1; i++){
            dist.push_back(ULONG_LONG_MAX);
            prev.push_back(-1);

        }
    }

    void input(int f, int t,ull d){

        side[f].push_back(mp(t, d));
        if(!DIRECTED) side[t].push_back(mp(f,d));
    }

    void search(int start){
        
        dist[start] = 0;
        prev[start] = 0;

        priority_queue<pair<ull,int>, vector<pair<ull,int>>, greater<pair<ull,int>>> pq;
        pq.push(mp(0,start));

        while(!pq.empty()){
            
            ull d = pq.top().first;
            int s = pq.top().second;

            for(auto itr = side[s].begin(); itr != side[s].end(); itr++){

                ull tmp_d = (*itr).second;
                int to = (*itr).first; 

                if(dist[to] > d + tmp_d){
                    dist[to] = d + tmp_d;
                    prev[to] = s;
                    pq.push(mp(d + tmp_d,to));
                }
            }

            pq.pop();
        }
    }

    ull min_distance(int to){
        return dist[to];
    }

};

int main(){

    int n,u,k;

    cin >> n;

    dijkstra dijk;
    dijk = dijkstra(n);

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

            scanf(" %d %llu",&v,&c);

            dijk.input(u,v,c);

        }
    }

    dijk.search(0);
    for(int i = 0; i < n; i++){
        cout << i << " " << dijk.min_distance(i) << endl;
    }
}