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()

	list := make([][]int, n)
	weight := make([]int, n)
	for i := range list {
		list[i] = make([]int, n)
		weight[i] = NIL
		for j := range list[i] {
			list[i][j] = NIL
		}
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		for j := 0; j < k; j++ {
			v := scanInt()
			w := scanInt()
			list[u][v] = w
		}
	}

	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 i, w := range list[node.id] {
			if w == NIL {
				continue
			}
			heap.Push(h, Node{id: i, weight: w + node.weight})
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		fmt.Fprint(w, i)
		fmt.Fprint(w, " ")
		fmt.Fprint(w, weight[i])
		fmt.Fprintln(w)
	}
	w.Flush()
}

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

int n;
int MAXIMUM=100;
int M[100][100];
int INF = 123456789;
// W:未訪問
// G:訪問する候補
// B:訪問済み
int W=0,G=1,B=2;
int dijkstra(){
  int u,minv;
  int d[MAXIMUM],color[MAXIMUM];
  // d[n]:Tに属する頂点と V - T に属する頂点をつなぐ辺の中で重みが最小の辺の重みを記録
  // p[i]: 頂点iからコスト最小となる親の頂点
  //初期化
  for(int i=0;i<n;i++){
    d[i]=INF;
    color[i]=W;
  }

  d[0]=0;
  color[0] = G;

  while (1) {
    minv = INF;
    u = -1;
    //訪問済みでない頂点の中で最もコストが低い辺を探す
    for(int i=0;i<n;i++){
      if(minv>d[i] && color[i]!=B){
        u=i;
        minv=d[i];
      }
    }
    // 頂点が見つからなかったら終了
    if(u==-1) break;
    // 頂点を訪問済に
    color[u] = B;
    //訪問済みでないかつ辺がつながっている頂点の中でコストが最小の辺を選択
    for(int v=0;v<n;v++){
      if(color[v]!=B && M[u][v]!=INF){
        if(d[v]>M[u][v] + d[u]){
          d[v] =M[u][v]+d[u];
          color[v]=G;
        }
      }
    }
  }

  for(int i=0;i<n;i++){
    if(d[i]!=INF) cout<<i<<" "<<d[i]<<endl;
    else cout<<i<<" "<<-1<<endl;
  }
}

int main(){
  cin>>n;
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      M[i][j]=INF;
    }
  }

  for(int i=0;i<n;i++){
    int u,k;
    cin>>u>>k;
    for(int j=0;j<k;j++){
      int v,c;
      cin>>v>>c;
      M[u][v]=c;
    }
  }

  dijkstra();

}

C++: #include<iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
	int minv;
	int d[MAX], color[MAX];

	for(int i=0;i<n;i++){
		d[i] = INFTY;
		color[i] = WHITE;
	}

	d[0] = 0;
	color[0] = GRAY;
	while(1){
		minv = INFTY;
		int u = -1;
		for(int i=0;i<n;i++){
			if(minv > d[i] && color[i] != BLACK){
				u = i;
				minv = d[i];
			}
		}
		if(u==-1) break;
		color[u] = BLACK;
		for(int v=0;v<n;v++){
			if(color[v] != BLACK && M[u][v] != INFTY){
				if(d[v] > d[u] + M[u][v]){
					d[v] = d[u] + M[u][v];
					color[v] = GRAY;
				}
			}
		}
	}

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

int main(){
	cin >> n;
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			M[i][j] = INFTY;
		}
	}

	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;
			M[u][v] = c;
		}
	}

	dijkstra();

	return 0;
}

C++: #include <climits>
#include <functional>
#include <iostream>
#include <queue>
#include <utility>
#include <vector>
using namespace std;

int main() {
	int n, u, k, v, c;
	cin >> n;
	vector<vector<pair<int, int>>> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> u >> k;
		for (int j = 0; j < k; ++j) {
			cin >> v >> c;
			a[u].emplace_back(v, c);
		}
	}
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> b;
	b.emplace(0, 0);
	vector<bool> d(n);
	vector<int> e(n, INT_MAX);
	e[0] = 0;
	while (!b.empty()) {
		pair<int, int> f = b.top();
		b.pop();
		d[f.second] = true;
		for (int i = 0; i < a[f.second].size(); ++i) {
			if (!d[a[f.second][i].first]) {
				if (a[f.second][i].second + e[f.second] < e[a[f.second][i].first]) {
					e[a[f.second][i].first] = a[f.second][i].second + e[f.second];
					b.emplace(e[a[f.second][i].first], a[f.second][i].first);
				}
			}
		}
	}
	for (int i = 0; i < n; ++i) cout << i << ' ' << e[i] << endl;
}

C++: #include <stdio.h>

using namespace std;


int main(){
	int n,count,t,min,min_index,tmp,left_node,right_node,dist;
	scanf("%d",&n);
	int distance[n][n],P[n];

	for(int i=0;i<n;i++){
		for(int k=0;k<n;k++)distance[i][k]=100001;
		P[i]=0;
	}
	distance[0][0] = 0;
	P[0]=1;

	for(int i=0;i<n;i++){
		scanf("%d %d",&left_node,&tmp);
		for(int k=0;k<tmp;k++){
			scanf("%d %d",&right_node,&dist);
			distance[left_node][right_node] = dist;
		}
	}

	while(count<n-1){

		min=100001;
		for(int i=1;i<n;i++){
			if(P[i]==0&&distance[0][i]<min){
				min_index = i;
				min = distance[0][i];
			}
		}
		t = min_index;
		P[t]=1;
		count++;

		for(int i=0;i<n;i++){
			if(distance[0][i] > distance[0][t]+distance[t][i]){
				distance[0][i]=distance[0][t]+distance[t][i];
			}
		}
	}

	for(int i=0;i<n;i++){
		printf("%d %d\n",i,distance[0][i]);
	}

    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;
static const int INF=(1<<21);
int n;
vector< pair<int,int> >adj[101];

void dijkstra(){
  priority_queue<pair<int,int> >pq;
  int color[101];
  int d[101];
  for(int i=0;i<n;++i){
    d[i]=INF;
    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(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]==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;
      adj[u].push_back(make_pair(v,c));
    }
  }
  dijkstra();
  return 0;
}