Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

const BIG_COST = 200000

type Path struct {
	node int
	cost int
}

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

	nNodes := scanInt(sc)

	// 各頂点につながる頂点一覧を得るための隣接リスト
	graph := make([][]Path, nNodes)

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[i] = make([]Path, k)
		for d := 0; d < k; d++ {
			graph[u][d] = Path{
				node: scanInt(sc),
				cost: scanInt(sc),
			}
		}
	}

	// 0 から各頂点への最小コストを保存する配列
	minCosts := make([]int, nNodes)

	minCosts[0] = 0
	for i := 1; i < nNodes; i++ {
		minCosts[i] = BIG_COST
	}

	// 各頂点が調査済みかどうかを保持する配列
	checked := make([]bool, nNodes)

	// 最小コストのパスを高速に取得するためのヒープ。
	// コストが小さいものほどルートに来るようにする。
	heap := NewHeap(func(a, b Path) bool {
		return a.cost < b.cost
	})

	heap.insert(Path{node: 0, cost: 0})
	for heap.size > 0 {
		u := heap.extractMax()

		// 隣接行列を使っていた時とは違い、ヒープには
		// 同じノードへのパスが複数含まれうる。そのため既によりコストの低い
		// パスが見つかっている場合は無視する。
		if minCosts[u.node] < u.cost {
			continue
		}

		checked[u.node] = true

		for _, v := range graph[u.node] {
			cost := v.cost + u.cost
			if !checked[v.node] && cost < minCosts[v.node] {
				minCosts[v.node] = cost
				heap.insert(Path{node: v.node, cost: cost})
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range minCosts {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

// --- From ALDS1_9_C: Priority Queue

type Heap struct {
	size   int
	heap   []Path
	isHigh func(a, b Path) bool
}

func NewHeap(isHigh func(a, b Path) bool) Heap {
	heap := make([]Path, 1) // 先頭は不使用
	return Heap{size: 0, heap: heap, isHigh: isHigh}
}

func (h *Heap) insert(v Path) {
	h.size += 1
	if h.size > len(h.heap)-1 {
		h.heap = append(h.heap, v)
	} else {
		h.heap[h.size] = v
	}

	for i := h.size; i > 1; {
		parent := i / 2
		if h.isHigh(h.heap[parent], h.heap[i]) {
			break
		}
		h.heap[i], h.heap[parent] = h.heap[parent], h.heap[i]
		i = parent
	}
}

func (h *Heap) extractMax() Path {
	if h.size <= 0 {
		panic("cannot extract from empty heap")
	}

	max := h.heap[1]
	h.heap[1] = h.heap[h.size]
	h.size -= 1
	h.maxHeapify(1)

	return max
}

func (h *Heap) maxHeapify(idx int) {
	left := idx * 2
	right := left + 1
	largest := idx

	if left <= h.size {
		if h.isHigh(h.heap[left], h.heap[idx]) {
			largest = left
		}
		if right <= h.size && h.isHigh(h.heap[right], h.heap[largest]) {
			largest = right
		}
	}

	if largest != idx {
		h.heap[idx], h.heap[largest] = h.heap[largest], h.heap[idx]
		h.maxHeapify(largest)
	}
}

C++: #include <bits/stdc++.h>
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 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();//(cost, Nodeid)
    int u = f.second;
    color[u] = BLACK;
    if( d[u] < f.first * ( -1 ))continue;//今の最小Nodeよりコストが大きいなら再計算はしない
    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));//STL priority_queueはmaximum
        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 <cstdio>
#include <cstring>
#include <vector>
#include <string>
#include <queue>
using namespace std;
const int INF = 1 << 30;
const int NIL = -1;
const int MAXN = 10005;
int vis[MAXN];
int d[MAXN];
int head[500005];
int n;
int cnt;
struct Edge {
	int to, next, w;
	Edge() {}
} edge[500005];

void add(int u, int v, int w)
{
	edge[cnt].to = v;
	edge[cnt].w = w;
	edge[cnt].next = head[u];
	head[u] = cnt++;
}

struct Node {
	int u, w;
	Node (int _u, int _w) :u(_u), w(_w) {}
	friend bool operator<(const Node& a, const Node& b)
	{
		return a.w > b.w;
	}
};

void dijkstra(int s)
{
	priority_queue<Node> q;
	for (int i = 0; i < n; ++i)
		d[i] = INF, vis[i] = false;
	d[s] = 0;
	
	Node t(s, 0);
	q.push(t);
	int u, v, w;
	int count = 0;
	while (!q.empty() && count < n - 1)
	{
		t = q.top();
		q.pop();
		u = t.u;
		if (d[u] < t.w)
			continue;
		vis[u] = true;
		++count;
		for (int i = head[u]; i != NIL; i = edge[i].next)
		{
			v = edge[i].to;
			w = edge[i].w;
			if (!vis[v] && d[v] > d[u] + w)
			{
				d[v] = d[u] + w;
				q.push(Node(v, d[v]));
			}
		}
	}
	if (count == n - 1)
		for (int i = 0; i < n; ++i)
			cout << i << " " << d[i] << endl;

}

int main(void)
{cin.tie(0);
	ios::sync_with_stdio(false);
	int k, s, e, w;
	cin >> n;
	memset(head, NIL, sizeof(-1));
	cnt = 0;
	for (int i = 0; i < n; ++i)
	{
		cin >> s >> k;
		while (k--)
		{
			cin >> e >> w;
			add(s, e, w);
		}
	}
	dijkstra(0);

	return 0;
}

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

class TNode
{
	std::list<std::pair<TNode*, int> > FNexts;
	int  FDistance;
public:
	TNode()
	: FDistance(-1)
	{
	}
	
	int GetDistance()const {return FDistance;}
	void SetDistance(int Distance){FDistance = Distance;}
	
	void Push(TNode* New, int Weight)
	{
		FNexts.push_back(std::make_pair(New, Weight));
	}
	
	void Visit()
	{
		std::cout << "Visited" << std::endl		for(std::list<std::pair<TNode*, int> >::iterator It = FNexts.begin(); It != FNexts.end(); ++It){
			int NextDistance = It->first->GetDistance();
			if(NextDistance >= 0 && NextDistance < FDistance + It->second) continue;
			It->first->SetDistance(FDistance + It->second);
		}
	}
};

class TGraph
{
	std::vector<TNode*> FNodes;
	std::list<TNode*> FSearchList;
	
	std::list<TNode*>::iterator FindMinimum()
	{
		std::list<TNode*>::iterator Result = FSearchList.begin();
		int Distance = (*Result)->GetDistance();
		for(std::list<TNode*>::iterator It = FSearchList.begin(); It != FSearchList.end(); ++It){
			int TempDistance = (*It)->GetDistance();
			if(Distance < 0 || TempDistance >= 0 && TempDistance < Distance){
				Result = It;
				Distance = TempDistance;
			}
		}
		return Result;
	}
public:
	TGraph(int Count)
	: FNodes(Count)
	{
		for(int i = 0; i < Count; ++i){
			FNodes[i] = new TNode();
			FSearchList.push_back(FNodes[i]);
		}
		FNodes[0]->SetDistance(0);
	}
	
	~TGraph()
	{
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			delete FNodes[i];
		}
	}
	
	void InputNode()
	{
		int Index;
		std::cin >> Index;
		int BranchCount;
		std::cin >> BranchCount;
		for(int i = 0; i < BranchCount; ++i){
			int Target, Weight;
			std::cin >> Target >> Weight;
			FNodes[Index]->Push(FNodes[Target], Weight);
		}
	}
	
	void DijkstraSearch()
	{
		while(!FSearchList.empty()){
			std::list<TNode*>::iterator It = FindMinimum();
			TNode* Minimum = *It;
			FSearchList.erase(It);
			Minimum->Visit();
		}
	}
	
	int Distance(int Target)const
	{
		return FNodes[Target]->GetDistance();
	}
};

int main()
{
	int Count;
	std::cin >> Count;
	TGraph Graph(Count);
	for(int i = 0; i < Count; ++i){
		Graph.InputNode();
	}
	Graph.DijkstraSearch();
	
	for(int i = 0; i < Count; ++i){
		std::cout << i << " " << Graph.Distance(i) << std::endl;
	}
	return 0;
}