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 <iostream>
#include <algorithm>
#include <queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<21);
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();


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();

}



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;

        // take the minimum value, ignore if it is not the shortest
        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;
                // multiple (-1) because of priority large value in priority_queue
                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] ) << '\n';
    }
}

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],i,j;
    int d[MAX];
    for(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(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(i=0;i<n;i++){
        cout << i << " " << (d[i]==INFTY ?-1:d[i]) << endl;
    }
}

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

C++: #include <bits/stdc++.h>
using namespace std;
static const int M=10000;
static const int INF=(1<<20);
int n;
vector<pair<int,int > > a[M];
void dijkstra(){
	priority_queue<pair<int,int> > Q;
	int col[M];
	int d[M];
	for(int i=0;i<n;i++){
		col[i]=0;
		d[i]=INF;
	}
	d[0]=0;col[0]=1;
	Q.push(make_pair(0,0));
	while(!Q.empty()){
		pair<int,int>f=Q.top();Q.pop();
		int u=f.second;col[u]=2;
		if(d[u]<f.first*(-1))continue;
		for(int j=0;j<a[u].size();j++){
			int v=a[u][j].first;
			if(col[v]==2)continue;
			if(d[v]>d[u]+a[u][j].second){
				d[v]=d[u]+a[u][j].second;
				Q.push(make_pair(d[v]*(-1),v));
				col[v]=1;
			}
		}
	}
	for(int i=0;i<n;i++)cout<<i<<' '<<(d[i]==INF?-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;
			a[u].push_back(make_pair(v,c));
		}
	}
	dijkstra();
}

C++: #include<iostream>
#include<cstdio>
#define INF 1<<30
#define MAX 1000000
using namespace std;
         
struct edge {
  int from,to,cost;
};
       
edge es[MAX];
       
int main(){
  int n,u,k,E,c,v;
  E = 0;
  scanf("%d",&n);
       
  for(int i=0;i<n;i++){
    scanf("%d %d",&u,&k);
          
    for(int j=0;j<k;j++){
      scanf("%d %d",&v,&c);
      es[E].from = u;
      es[E].to = v;
      es[E++].cost = c;
    }
  }
  int d[MAX];
  for(int i=0;i<n;i++)d[i] = INF;
  d[0] = 0;
  while(true){
    int j=0;
    for(int i=0;i<E;i++){
      edge e = es[i];
      if(d[e.from] != INF && d[e.to] > d[e.from] + e.cost){
    d[e.to] = d[e.from] + e.cost;
    j=1;
      }
    }
    if(j==0)break;
  }
  for(int i=0;i<n;i++)cout << i << " " << d[i] << endl;
  return 0;
}

C++: #include <algorithm>
#include <iostream>
#include <queue>
#include <cstdio>
using namespace std;

static const int Max = 100;
static const int Inf = 10000000;
enum State {
	Not_Searched = 0,
	Connected = 1,
	Searched = 2
};

int n = 0;
vector<pair<int, int> > adj[Max]; // pair<??£??\??????index, ??????cost> 

void dijkstra() {
	priority_queue<pair<int, int> > pq; // pair<start ???????????????????????????????????§????????????????´???????idx>
	int st[Max];
	int min_cost[Max];
	for (int i = 0; i < n; i++) {
		st[i] = Not_Searched;
		min_cost[i] = Inf;
	}

	min_cost[0] = 0;
	pq.push(make_pair(0, 0));
	st[0] = Connected;

	while (!pq.empty()) {
		pair<int, int> f = pq.top();
		pq.pop();
		int u = f.second;
		st[u] = Searched;

		if (min_cost[u] < f.first * (-1)) continue;

		for (int i = 0; i < adj[u].size(); i++) {
			int adj_u_idx = adj[u][i].first;
			if (st[adj_u_idx] == Searched) continue;
			if (min_cost[adj_u_idx] > min_cost[u] + adj[u][i].second) {
				min_cost[adj_u_idx] = min_cost[u] + adj[u][i].second;
				pq.push(make_pair(min_cost[adj_u_idx]*(-1), adj_u_idx));
				st[adj_u_idx] = Connected;
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << " " << (min_cost[i] == Inf ? -1 : min_cost[i]) << endl;
	}
	return;
}

int main() {
	cin >> n;
	int u, k, vi, ci;
	for (int i = 0; i < n; i++) {
		scanf("%d %d", &u, &k);
		//cin >> u >> k;
		for (int j = 0; j < k; j++) {
			scanf("%d %d", &vi, &ci);
			//cin >> vi >> ci;
			adj[u].push_back(make_pair(vi, ci));
		}
	}

	dijkstra();
	return 0;
}