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++: // 単一始点最短経路 ( ダイクストラ法 : 優先度付きキュー )
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<stack>
#include<algorithm>
#include<iostream>
#include<cmath>
#include<vector>

#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;

// 重み付き有向グラフの隣接リスト表現
// first : 頂点No. second : 入力される辺の重み
vector< pair<int, int> > adj[MAX];

int Dijkstra()
{
    int u;
    int d[MAX], p[MAX], color[MAX];

    // 優先度付きキュー : first : 最短距離 second : 頂点No.
    priority_queue< pair<int, int> > PQ;

    for(int i = 0; i < n; i++)
    {
        d[i] = INFTY;
        p[i] = -1;
        color[i] = WHITE;
    }

    // 初期値の設定
    d[0] = 0;
    PQ.push( make_pair(0, 0) );
    color[0] = GRAY;

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

        // 次に移動するべき頂点
        u = f.second;;
        // 訪問完了
        color[u] = BLACK;

        // 最小値を取り出し, それが最短で無ければ無視
        if( d[u] < f.first * (-1) )
        {
            continue;
        }

        for(int j = 0; j < adj[u].size(); j++)
        {
            // 隣接リストから要素を取得する
            int v = adj[u][j].first;

            if( color[v] != BLACK )
            {
                // u → v の経路の中で, vのコストが最小のものが見つかれば更新する
                if( d[v] > d[u] + adj[u][j].second )
                {
                    // コストの記録
                    d[v] = d[u] + adj[u][j].second;
                    // 頂点 v の親を記録する
                    p[v] = u;
                    // 訪問状態の記録
                    color[v] = GRAY;

                    // キューに要素を入れる
                    // priority_queue はデフォルトで大きい値を優先するため, -1を掛ける
                    PQ.push( make_pair( d[v] * (-1), v ) );
                }
            }
        }
    }

    // 結果の表示
    for(int i = 0; i < n; i++)
    {
        cout << i << " " << ( d[i] == INFTY ? -1 : d[i] ) << endl;
    }

    return 0;
}

int main(void)
{

    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<bits/stdc++.h>
#define REP(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;

struct edge { int from, to, cost; };
const int MAX_V=100;
const int INF=1e9;

vector<edge> es;
int d[MAX_V];
int n;

void shortest_path(int s){
  REP(i, n) d[i] = INF;
  d[s] = 0;
  while(true){
    bool update = false;
    for(edge e : es){
      if(d[e.from] != INF && d[e.to] > d[e.from] + e.cost){
	d[e.to] = d[e.from] + e.cost;
	update = true;
      }
    }
    if(!update) break;
  }
}

int main(){
  cin>>n;
  REP(i,n){
    int u, k; cin>>u>>k;
    REP(j,k){
      edge e;
      e.from = u;
      cin>>e.to>>e.cost;
      es.push_back(e);
    }
  }
  shortest_path(0);
  REP(i,n){
    cout<<i<<" "<<d[i]<<endl;
  }
}