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;
#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;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
using namespace std;

const int NOTV = 0;
const int VIST = 1;
const int NMAX = 10000;
//const int VMAX = 2000;
const int NILL = -1;
const int INF = 1 << 21;
//int a[NMAX][NMAX];  //??£??\??????
int n;
vector<pair<int, int> > adj[NMAX];

void dijkstra() {
	int d[NMAX];
	int vst[NMAX];
	priority_queue<pair<int, int> > pq;
	for (int i = 0; i < n; i++) {
		vst[i] = NOTV;
		d[i] = INF;
	}
	d[0] = 0;
	pq.push(make_pair(d[0], 0));
	while (not pq.empty()) {
		pair<int, int> f = pq.top(); pq.pop();
		int u = f.second;
		vst[u] = VIST;
		if (d[u] < f.first*(-1)) continue;
		for (int i = 0; i < adj[u].size(); i++) {
			int v = adj[u][i].first;
			if (vst[v] == NOTV) {
				if (d[u] + adj[u][i].second < d[v]) {
					d[v] = d[u] + adj[u][i].second;
					pq.push(make_pair(d[v] * (-1), v));
				}
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << ' ' << d[i] << endl;
	}
}

int main() {
	cin >> n;
	int k, u, v, c;
	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;
}