Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = j
	pq[j].index = i
}

func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 //for safety
	*pq = old[0 : n-1]
	return item
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist *[][]int, n int) *[]int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range (*dist)[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return &shortests
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(&dist, n)
	for i, d := range *shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

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

const int MAX = 100;
const int INFINITY = 2 << 21;
int n;
int G[MAX][MAX];
int distances[MAX];
int states[MAX];

void dijkstra() {
  int id = 0;
  distances[id] = 0;

  while (1) {
    int min = INFINITY;

    for (int i = 0; i < n; i++) {
      if (states[i] == 0 && distances[i] < min) {
        min = distances[i];
        id = i;
      }
    }

    if (min == INFINITY) break;

    for (int i = 0; i < n; i++) {
      if (states[i] != 0 || G[id][i] == -1) continue;
      if (distances[id] + G[id][i] < distances[i]) {
        distances[i] = distances[id]+ G[id][i];
      }
    }

    states[id] = 1;
  }

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

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  cin >> n;

  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) G[i][j] = INFINITY;
  }

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

  dijkstra();

  return 0;
}

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];
  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;
 
    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;
        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] ) << 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;
}

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>

#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define repi(i,a,b) for(int i = (a); i < (b); i++)

using namespace std;

typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;

const int INF=1<<29;
const double EPS=1e-9;

const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};
const int MAX_N =10000;

struct edge
{
	int to,cost;
	edge(int _to,int _cost){
		to =_to;
		cost =_cost;
	}
};

int V;
vector<edge> cost[MAX_N];
int d[MAX_N];
bool visit[MAX_N];
void dijkstra(int s){
	d[s]=0;
	priority_queue<pii, vector<pii> ,greater<pii> > que;
	que.push(mp(0,s));
	while(!que.empty()){
		pii p =que.top();
		que.pop();
		int v =p.second;
		if(d[v] < p.first)continue;
		for(int i =0;i <cost[v].size();i++){
			edge e =cost[v][i];
			if(d[e.to] >d[v]+e.cost){
				d[e.to] =d[v] +e.cost;
				que.push(mp(d[e.to],e.to));
			}
		}
	}
}

int main(){
	cin>>V;
	for(int i =0;i <V;i++){
		d[i]=INF;
		int u,k;
		cin>>u>>k;
		for(int j =0;j <k;j++){
			int to,c;
			cin>>to>>c;
			cost[u].push_back(edge(to,c));
		}
	}
	
	dijkstra(0);
	for(int i =0;i <V;i++){
		cout <<i<<" "<<d[i]<<endl;
	}
	return 0;
}