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<iostream>
#include<cstdio>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;

#define INF 20000000
typedef struct Edge edge;

struct Edge{
  int src,dst,weight;
  Edge(int start,int end,int cost) :
	src(start),dst(end),weight(cost) {}
};

bool operator < (const edge &e,const edge &f){
  return (e.weight != f.weight) ? (e.weight > f.weight) : (e.src != f.src) ? (e.src < f.src) : (e.dst < f.dst);
}

typedef vector<edge> Edges;

vector<int> dijkstra(Edges,int);

int main(int argc,char* argv[]){
  int n,v,k,dst,weight;
  Edges es;
  vector<int> vec;

  cin >> n;
  for(int i = 0;i < n;i++){
	cin>> v >> k;
	vec.push_back(v);
	for(int j = 0;j < k;j++){
	  cin >> dst >> weight;
	  edge e(i,dst,weight);
	  es.push_back(e);
	}
  }

  vector<int> dist = dijkstra(es,n);

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

vector<int> dijkstra(Edges es,int n){
  vector<int> dist(n);
  priority_queue<edge> que;
  Edges l[n];
  dist.assign(n,INF);
  dist[0] = 0;

  for(int i = 0;i < (int)es.size();i++){
	edge e = es[i];
	l[e.src].push_back(e);
  }

  for(int i = 0;i < (int)l[0].size();i++)
	que.push(l[0][i]);

  while(!que.empty()){
	edge e = que.top();
	que.pop();
	if(dist[e.dst] > dist[e.src] + e.weight){
	  dist[e.dst] = dist[e.src] + e.weight;

	  for(int i = 0;i < (int)l[e.dst].size();i++)
		que.push(l[e.dst][i]);
	}
  }

  return dist;
}

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 min;
   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 ) {
      min = INFTY; 
      int a = -1;
      for ( int i = 0; i < n; i++ ) {
         if ( min > d[i] && color[i] != BLACK ) {
             a = i;
             min = d[i];
         }
      }

      if ( a == -1 ) break;
      color[a] = BLACK;
      
      for ( int v = 0; v < n; v++ ) {
         if ( color[v] != BLACK && M[a][v] != INFTY ) {
            if ( d[v] > d[a] + M[a][v] ) {
               d[v] = d[a] + M[a][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 < n; j++ ) {
      cin >> v >> c;
      M[u][v] = c;
      }
   }

   dijkstra();

   return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <climits>
#include <cstring>

using namespace std;

#define SWAP(type, a, b) do { type t = a; a = b; b = t; } while(0)

typedef struct {
    int* verIdx;
    int num;
} Heap;

int* d; 
int* weight;
int n;

void makeMinHeap(Heap *heap, int idx);
void insert(Heap *heap, int key);
int extract(Heap *heap);

static inline int getParent(int idx) { return idx / 2; }
static inline int getLeft(int idx) { return idx * 2; }
static inline int getRight(int idx) { return idx * 2 + 1; }
static inline bool isCorrectHeapIdx(int idx, int heapSize) { return idx <= heapSize && 1 <= idx; }
static inline bool isEmpty(Heap *heap) { return heap->num <= 0; }

static inline int getMinCost(int idx) {
    return d[idx];
}

void makeMinHeap(Heap *heap, int idx) {
    int left = getLeft(idx);
    int right = getRight(idx);

    int minIdx = idx;
    if(isCorrectHeapIdx(left, heap->num) && getMinCost(heap->verIdx[minIdx]) > getMinCost(heap->verIdx[left])) {
        minIdx = left;
    } if(isCorrectHeapIdx(right, heap->num) && getMinCost(heap->verIdx[minIdx]) > getMinCost(heap->verIdx[right])) {
        minIdx = right;
    }

    if(minIdx != idx) {
        SWAP(int, heap->verIdx[minIdx], heap->verIdx[idx]);
        makeMinHeap(heap, minIdx);
    }
}

void insert(Heap *heap, int* key) {
    heap->verIdx[++heap->num] = *key;
    for(int i = getParent(heap->num); i >= 1; i = getParent(i)) {
        makeMinHeap(heap, i);
    }
}

void extract(Heap *heap, int* key) {
    *key = heap->verIdx[1];
    heap->verIdx[1] = heap->verIdx[heap->num--];
    makeMinHeap(heap, 1);
}

static inline bool isConnected(int s, int t) {
    return weight[s * n + t] != INT_MAX;
}

static inline int getWeight(int s, int t) {
    return weight[s * n + t];
}

void solve(int s) {
    Heap que;
    bool* isAddS = new bool[n]();

    que.verIdx = new int[n * n];
    que.num = 0;

    d = new int[n];
    d[s] = 0;
    for(int i = 0; i < n; i++) {
        if(s != i) {
            d[i] = INT_MAX;
        }
    }
    
    insert(&que, &s);

    while(1) {
        int u;
        while(1) {
            if(isEmpty(&que)) {
                return;
            } 

            extract(&que, &u);
            if(!isAddS[u]) {
                break;
            }
        }

        isAddS[u] = true;

        for(int i = 0; i < n; i++) {
            if(isConnected(u, i) && !isAddS[i]) {
                if(d[u] + getWeight(u, i) < d[i]) {
                    d[i] = d[u] + getWeight(u, i);
                }
                insert(&que, &i);
            }
        }
    }

    return;
}

int main() {

    scanf("%d", &n);

    weight = new int[n * n];

    for(int i = 0; i < n * n; i++) {
        weight[i] = INT_MAX;
    }
    

    for(int i = 0; i < n; i++) {
        int s;
        int deg;

        scanf("%d %d", &s, &deg);
        for(int j = 0; j < deg; j++) {
            int t;
            int w;

            scanf("%d %d", &t, &w);

            weight[s * n + t] = w;
        }
    }

    solve(0);

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