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 <stdio.h>
#include <iostream>
#include <queue>
#include <vector>
using namespace std;

#define NIL -1
#define INF 100000000
#define WHITE 1
#define GREY 2
#define BLACK 3
#define N_MAX 10000

vector<pair<int, int>> G[N_MAX];
int V[N_MAX];
int V_value[N_MAX];

void init(){
    for(int i = 0; i < N_MAX; i++){
        V[i] = WHITE;
        V_value[i] = INF;
    }
}

int main(void){
    init();
    int n;
    scanf("%d\n", &n);

    for(int i = 0; i < n; i++){
        int u, k;
        scanf("%d %d", &u, &k);
        for(int j = 0; j < k; j++){
            int v, c;
            scanf("%d %d", &v, &c);
            G[u].push_back(make_pair(v, c));
        }
    }

    priority_queue<pair<int, int>> PQ;

    V[0] = BLACK;
    V_value[0] = 0;
    int new_node = 0;
    
    while(1){
        for(int i = 0; i < G[new_node].size(); i++){
            int node_num = G[new_node][i].first;
            int node_value = G[new_node][i].second;
            V_value[node_num] = min(V_value[node_num], V_value[new_node] + node_value);
            PQ.push(make_pair(V_value[node_num] * (-1), node_num));
        }

        int min_value;
        int min_index = NIL;
        while(!PQ.empty()){
            pair<int, int> p = PQ.top(); PQ.pop();
            //printf("pop %d %d\n", p.second, p.first * (-1));
            if(p.first * (-1) == V_value[p.second] && V[p.second] == WHITE){
                min_value = p.first * (-1);
                min_index = p.second;
                break;
            }
        }

        if(min_index == NIL)
            break;

        new_node = min_index;
        V[new_node] = BLACK;
        V_value[new_node] = min_value;
    }
    
    for(int i = 0; i < n; i++){
        printf("%d %d\n", i, V_value[i]);
    }

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
static const int MAX = 10000;
int N;
vector<pair<int, int>> adj[MAX];
int color[MAX];
int d[MAX];
int INF = 1 << 30;

void pd() {
    for (int i = 0; i < N; i++) {
        cout << d[i] << " ";
    }
    cout << endl;
}

void pa() {
    for (int i = 0; i < N; i++) {
        cout << i << " ";
        for (int j = 0; j < adj[i].size(); j++) {
            cout << adj[i][j].second << " ";
        }
        cout << endl;
    }
    cout << endl;
}

void dijkstr() {
    int i,j;
    priority_queue<pair<int, int>> PQ;
    PQ.push(make_pair(0, 0));
    
    d[0] = 0;
    cout << N << endl;
    for (i = 0; i < N; i++) {
        pair<int, int> p = PQ.top(); PQ.pop();
        
        //int c = p.first;
        int id = p.second;
        
        color[id] = 1;
        for (j = 0; j < adj[id].size(); j++) {
            auto node = adj[id][j];
            int c = node.first;
            int k = node.second;
            if (color[k] != 1) {
                if (d[k] > d[id] + c) {
                    d[k] = d[id] + c;
                    PQ.push(make_pair(-c, k));
                }
            }
        }
    }
}



int main(int argc, const char * argv[]) {
    int i,j;
    cin >> N;
//    pd();

    for (i = 0; i < N; i++) {
        int u,k;
        cin >> u >> k;
        color[i] = 0;
        d[i] = INF;
        for (j = 0; j < k; j++) {
            int v, c;
            cin >> v >> c;
            adj[u].push_back(make_pair(c, v));
        }
    }
    
    //pa();
    
    dijkstr();
    
    for (i = 0; i < N; i++) {
        cout << i << " " << d[i] << endl;
    }
    
    
    return 0;
}

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

const int MAX=10005;
int state[MAX],N,D[MAX];
vector<pair<int,int>> S[MAX];
priority_queue<pair<int,int>> Q;

void dijkstra(){
    int cnt=1;
    for(int i=0;i<N;i++){
        state[i]=0;
        D[i]=100000000;
    }
    state[0]=1;
    D[0]=0;
    for(int i=0;i<S[0].size();i++){
        Q.push(make_pair(-S[0][i].second,S[0][i].first));
        D[S[0][i].first]=min(D[S[0][i].first],D[0]+S[0][i].second);
    }
    while(1){
        int a=Q.top().second;
            if(state[a]==0){
            Q.pop();
            state[a]=1;
            cnt++;
            for(int i=0;i<S[a].size();i++){
                if(state[S[a][i].first]==0){
                    Q.push(make_pair(-S[a][i].second,S[a][i].first));
                    D[S[a][i].first]=min(D[S[a][i].first],D[a]+S[a][i].second);
                }
            }
        }
        else Q.pop();
        if(cnt==N) break;
    }
    return;
}


int main(){
   
    cin>>N;
    for(int i=0;i<N;i++){
        int l,a;cin>>l>>a;
        for(int j=0;j<a;j++){
            int b,c;cin>>b>>c;
            S[i].push_back(make_pair(b,c));
        }
    }
    dijkstra();
    for(int i=0;i<N;i++){
        cout<<i<<" "<<D[i]<<endl;
    }
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
using namespace std;
#define MAX 10000
#define INFTY (1<<30)
#define rep(i,n)	for(int i=0;i<n;i++)
enum{
	white,
	gray,
	black,
};

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

void dijkstra(){
	priority_queue<pair<int,int> >	pq;
	int color[MAX];
	int d[MAX];
	rep(i,n){
		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;
		rep(j,(int)adj[u].size()){
			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;
			}
		}
	}
	rep(i,n){
		cout<<i<<" "<<(d[i]==INFTY?-1:d[i])<<endl;
	}
}

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