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 <stdio.h>
#define INF 10000000
typedef struct{
	int node;
	int cost;
} List;

int dist[101];
List list[101][101];
int kazu[101];

int n;

void walk(int x,int step){
	dist[x]=step;
	for(int i=0;i<kazu[x];i++){
		if(dist[list[x][i].node]>step+list[x][i].cost) walk(list[x][i].node,step+list[x][i].cost);
	}
}

int main(void){
	int i,j,w;
	int num;
	scanf("%d",&n);
	for(i=0;i<n;i++){
		scanf("%d",&num);
		scanf("%d",kazu+num);
		for(j=0;j<kazu[num];j++)scanf("%d %d",&(list[num][j].node),&list[num][j].cost);
	}
	for(i=0;i<n;i++) dist[i]=INF;
	walk(0,0);
	
	for(i=0;i<n;i++){
		printf("%d %d\n",i,dist[i]);
	}
	return 0;
}

C++: #include <iostream>
#include <limits>
#define N 100

using namespace std;

const int INF=numeric_limits<int>::max();

int n,M[N][N],d[N];

void dijkstra(int s){
  bool visited[n];
  for(int i=0;i<n;i++){
    visited[i]=false;
    d[i]=INF;
  }
  d[s]=0;
  while(1){
    int mincost=INF;
    int u;
    //find minimum d from non-visited nodes
    for(int i=0;i<n;i++){
      if(!visited[i] && d[i]<mincost){
        mincost=d[i];
        u=i;
      }
    }
    if(mincost==INF) break;

    visited[u]=true;
    //update d
    for(int v=0;v<n;v++){
      if(!visited[v] && M[u][v]!=INF){
        if(d[u]+M[u][v]<d[v]){
          d[v]=d[u]+M[u][v];
        }
      }
    }
  }
}

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 i=0;i<k;i++){
      int v,c; cin >> v >> c;
      M[u][v]=c;
    }
  }
  dijkstra(0);
  for(int i=0;i<n;i++)
    cout << i << " " << d[i] << endl;
}