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<algorithm>
#include<iostream>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<vector>
#include<queue>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
using namespace std;

//typedef vector<int> VI;
//typedef vector<VI> VVI;
//typedef vector<string> VS;
//typedef stack<int> SI;
//typedef queue<int> QI;
typedef pair<int,int> PII;
//typedef long long LL;

//#define d(x)  cout<<#x<<" = "<<(x)<<endl;
//#define ALL(a)  (a).begin(),(a).end()
//#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define EMP empty()
#define SZ(a) int((a).size())
//#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
//#define REACH(i,c) for(typeof((c).rbegin()) i=(c).rbegin(); i!=(c).rend(); ++i)
//#define EXIST(s,e) ((s).find(e)!=(s).end())
//#define SORT(c,n) sort(c,c+n)
//#define VSORT(c) sort((c).begin(),(c).end())
//#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
//#define DFOR(i,b,a) for(int i=(b)-1;i>=(a);--i)
//#define DREP(i,n) DFOR(i,n,0)
//#define INF 1000000000

//const double EPS = 1e-10;
//const double PI  = acos(-1.0);
////////////////////////////////////////////////
static const int MAX=10000;
static const int INF=(1<<20);
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;

int n;
vector<PII> adj[MAX];
void dijkstra()
{
	priority_queue<PII> PQ;
	int color[MAX];
	int d[MAX];
	REP(i,n)
	{
		d[i]=INF;
		color[i]=WHITE;
	}
	
	d[0]=0;
	PQ.push(MP(0,0));
	color[0]=GRAY;
	
	while(!PQ.EMP)
	{
		PII f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=BLACK;
		
		if(d[u]<f.first*(-1))continue;
		
		REP(j,SZ(adj[u]))
		{
			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(MP(d[v]*(-1),v));
			color[v]=GRAY;
		}
	}
	REP(i,n)
	{
		cout<<i<<" "<<(d[i]==INF?-1:d[i])<<endl;
	}
}

int main()
{
	int k,u,c,v;
	cin>>n;
	REP(i,n)
	{
		cin>>u>>k;
		REP(j,k)
		{
			cin>>v>>c;
			adj[u].PB(MP(v,c));
		}
	}
	
	dijkstra();
	
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#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;

vector<pair<int,int> > adj[MAX];

void dijkstra(){
  priority_queue<pair<int,int> > PQ;
  int color[MAX];
  int d[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(){
  int k,u,v,c;
  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<cstdio>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<stack>
#include<vector>
#include<queue>
#define INFTY 500000
#define WHITE 0
#define GRAY 1
#define BLACK 2
using namespace std;

int color[12000],d[12000];
vector<pair<int,int> > v[12000];
priority_queue<pair<int,int> > PQ;
int n;

void start(int x){
  d[x]=0;
  PQ.push(make_pair(0,0));
  while(!PQ.empty()){
    pair<int,int> f;
    f=PQ.top();
    PQ.pop();
    int u=f.second;
    if(f.first*(-1) > d[u]) continue;
    color[u]=BLACK;
    for(int i=0;i<v[u].size();i++){
      int temp=v[u][i].first;
      if(d[temp]>d[u]+v[u][i].second && color[temp]!=BLACK){
        d[temp]=d[u]+v[u][i].second;
        color[temp]=GRAY;
        PQ.push(make_pair(-1*d[temp],temp));
      }
    }
  }
  for(int i=0;i<n;i++){
    cout<<i<<" "<<d[i]<<endl;
  }
}

int main(){
  int u,k,v1,c;
  cin>>n;
  for(int i=0;i<n;i++){
    d[i]=INFTY;
  }
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++){
      cin>>v1>>c;
      v[u].push_back(make_pair(v1,c)); 
    }
  }
  start(0);
}

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

using namespace std;

typedef pair<int,int> PII;
#define INF 1001001001
#define rep(i,n) for(int i=0; i<n; ++i)
#define mp make_pair

struct edge{
    short to;
    short cost;
    edge(short to,short cost):to(to),cost(cost){}
};

int V;
vector<edge> G[10000];
int d[10000];

void dijkstra(int s){
    priority_queue<PII, vector<PII>, greater<PII>> Q;
    fill(d,d+V,INF);
    d[s]=0;
    Q.push(mp(0,s));

    while(!Q.empty()){
        PII p=Q.top();Q.pop();
        int v=p.second;
        if(d[v]<p.first) continue;
        rep(i,G[v].size()){
            edge e=G[v][i];
            if(d[e.to]>d[v]+e.cost){
                d[e.to]=d[v]+e.cost;
                Q.push(mp(d[e.to],e.to));
            }
        }
    }
}
int n;
int main(){
    cin>>V;
    rep(i,V){
        rep(j,V){
            int u,k;
            cin>>u>>k;
            rep(t,k){
                int v, c;
                cin>>v>>c;
                G[u].push_back(edge(v,c));
            }
        }
    }
    dijkstra(0);
    rep(i,V){
        cout<<i<<" "<<d[i]<<endl;
    }
    return 0;
}