Go: package main

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

type Node struct {
	Id int
	Dis int
}

type PriorityQueue []*Node

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

func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].Dis < pq[j].Dis
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}

func (pq *PriorityQueue) Push(x interface{}) {
	*pq = append(*pq, x.(*Node))
}

func (pq *PriorityQueue) Pop() interface{} {
	n := len(*pq)
	pop := (*pq)[n-1]
	*pq = (*pq)[0:n-1]
	return pop
}

func main() {
	var n int
	fmt.Scan(&n)

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

	g := make([][]int, n)
	c := make([][]int, n)
	pq := make(PriorityQueue, 0, n)
	d := make([]int, n)
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		g[u] = make([]int, k)
		c[u] = make([]int, k)
		for j := 0; j < k; j++ {
			sc.Scan()
			g[u][j], _ = strconv.Atoi(sc.Text())
			sc.Scan()
			c[u][j], _ = strconv.Atoi(sc.Text())
		}

		if u == 0 {
			d[u] = 0
		} else {
			d[u] = 1 << 30
		}
		pq.Push(&Node{u, d[u]})
	}
	heap.Init(&pq)

	for pq.Len() > 0 {
		node := heap.Pop(&pq).(*Node)
		for i := 0; i < len(g[node.Id]); i++ {
			nextId := g[node.Id][i]
			nextDis := node.Dis + c[node.Id][i]
			if nextDis < d[nextId] {
				d[nextId] = nextDis
				heap.Push(&pq, &Node{nextId, nextDis})
			}
		}
	}

	wr := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		wr.WriteString(strconv.Itoa(i))
		wr.WriteString(" ")
		wr.WriteString(strconv.Itoa(d[i]))
		wr.WriteString("\n")
	}
	wr.Flush()
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <climits>
#include <queue>
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define repR(i, n) for(int i = (n) - 1; i > -1; i--)
#define rep1(i, n) for(int i = 1; i < (int)(n + 1); i++)
#define rep1R(i, n) for(int i = (n); i > 0; i--)
using namespace std;
static const int MAX = 10010;
static const int INF = INT_MAX;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

struct Node {
  int v, c;
};

bool operator > (const Node& v1, const Node& v2) {
  return v1.c > v2.c;
}

vector<Node> adj[MAX];
int color[MAX];
int d[MAX];
int n;

void dijkstra(int s) {
  rep(u, n) {
    color[u] = WHITE;
    d[u] = INF;
  }
  d[s] = 0;

  priority_queue<Node, vector<Node>, greater<Node>> PQ;
  PQ.push(Node{s, 0});

  while (!PQ.empty()) {
    Node n = PQ.top(); PQ.pop();
    int u = n.v;
    int c = n.c;

    color[u] = BLACK;

    if (d[u] < c) continue;

    rep(i, adj[u].size()) {
      Node nextNode = adj[u][i];
      int v = nextNode.v;
      if (color[v] != BLACK) {
        if (d[u] + nextNode.c < d[v]) {
          d[v] = d[u] + nextNode.c;
          color[v] = GRAY;
          PQ.push(Node {v, d[v]});
        }
      }
    }
  }
}

int main() {
  cin >> n;
  rep(i, n) {
    int u, k;
    cin >> u >> k;
    rep(j, k) {
      int v, c;
      cin >> v >> c;
      adj[u].push_back(Node {v, c});
    }
  }
  dijkstra(0);
  rep(v, n) cout << v << " " << d[v] << endl;
  return 0;
}

C++: #include<iostream>
#include<string>
#include<algorithm>
#include<queue>
#include<vector>
#include<stack>
using namespace std;
#define MAX 10000
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define INFTY (1<<30)
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(){
  cin >> n;

  int k,c,u,v;
  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 <cstdio>
#include <string>
#include <list>
#include <stack>
#include <queue>
#include <algorithm>
#include <utility>
#include <vector>
#include <map>
#include <bitset>

using namespace std;

int main()
{
	int N;
	cin>>N;
	
	vector<vector<int> > cost(N,vector<int>(N,10000001));
	cost[0][0]=0;
	pair<int,int> ddata;
	for(int i=0;i<N;i++){
		int u,k;
		cin>>u>>k;
		for(int j=0;j<k;j++){
			cin>>ddata.first>>ddata.second;
			cost[u][ddata.first]=ddata.second;
		}
	}
	//
	
	vector<int> maxcost(N,10000001);
	
	priority_queue<pair<int,int>, vector<pair<int,int> >, greater<pair<int,int> > > que;
	
	que.push(pair<int,int>(0,0));
	
	while(!que.empty()){
		int n=que.top().second;
		if(que.top().first<maxcost[n]){
			maxcost[n]=que.top().first;
		}//*/
		for(int j=1;j<N;j++){
			if(j!=n&&maxcost[n]+cost[n][j]<maxcost[j]){
				maxcost[j]=maxcost[n]+cost[n][j];
				ddata.first=maxcost[n]+cost[n][j];
				ddata.second=j;
				que.push(ddata);
			}
		}
		que.pop();
	}
	
	for(int i=0;i<N;i++){
		cout<<i<<' '<<maxcost[i]<<endl;
	}
	return 0;
}

C++: #include<iostream>
#include<cstdlib>
#include<cstdio>
#define N 100001
#define INF 1000000009
using namespace std;

struct Heap{
  int key,cost;
};

struct node{
  int key,cost;
  node *prev,*next;
};

node *nil[N];
int n,d[N];
Heap A[N];

void init(){
  for(int i=0;i<n;i++){
  nil[i] = (node *)malloc(sizeof(node));
  nil[i]->next =nil[i];
  nil[i]->prev=nil[i];
  }
}

void insert(int i,int key,int cost){
  node *x= (node *)malloc(sizeof(node));
  x->key = key,x->cost=cost;
  x->next = nil[i]->next;
  nil[i]->next->prev = x;
  nil[i]->next = x;
  x->prev = nil[i];
}

int size;
void increase(int i,int key,int cost){
  Heap tmp;
  A[i].key=key,A[i].cost=cost;
  while(i>1 && A[i/2].cost > A[i].cost)tmp=A[i],A[i]=A[i/2],A[i/2]=tmp,i=i/2;
}

void insert(int key,int cost){
  size++,A[size].key=INF,A[size].cost=INF;
  increase(size,key,cost);
  }

void minHeapify(int i){
  int l,r,min;
  Heap tmp;
 l=i*2;
  r=i*2+1;
  if(l<=size && A[l].cost<A[i].cost)min=l;
  else min=i;
  if(r<=size && A[r].cost<A[min].cost)min=r;
  if(min!=i){tmp=A[i],A[i]=A[min],A[min]=tmp; minHeapify(min);}
}


Heap extractMin(){
  Heap min;
  min=A[1],A[1]=A[size],size--,minHeapify(1);
  return min;
}

void dijkstra(int s){
  Heap u;
  int used[N];
  for(int i=0;i<n;i++) used[i]=0,d[i]=INF;
  d[s]=0;
  while(size>=1){
    u=extractMin();
    used[u.key]=2;
    if(d[u.key] <u.cost)continue;
    node *v=nil[u.key]->next;
    while(v!=nil[u.key]){
      if(used[v->key]!=2)
	if(d[u.key]+v->cost<d[v->key])
	  d[v->key]=d[u.key]+v->cost,used[v->key]=1,insert(v->key,d[v->key]);
      v=v->next;
    }
  }
}

int main(){
  cin>>n;
  init();
  int u,k,v,c;
  size=n;
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++){
      cin>>v>>c;
      insert(u,v,c);
    }
  }
   dijkstra(0);
  for(int i=0;i<n;i++)cout<<i<<" "<<d[i]<<endl;
  
  return 0;
}