Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

const BIG_COST = 200000

type Path struct {
	node int
	cost int
}

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

	nNodes := scanInt(sc)

	// 各頂点につながる頂点一覧を得るための隣接リスト
	graph := make([][]Path, nNodes)

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[i] = make([]Path, k)
		for d := 0; d < k; d++ {
			graph[u][d] = Path{
				node: scanInt(sc),
				cost: scanInt(sc),
			}
		}
	}

	// 0 から各頂点への最小コストを保存する配列
	minCosts := make([]int, nNodes)

	minCosts[0] = 0
	for i := 1; i < nNodes; i++ {
		minCosts[i] = BIG_COST
	}

	// 各頂点が調査済みかどうかを保持する配列
	checked := make([]bool, nNodes)

	// 最小コストのパスを高速に取得するためのヒープ。
	// コストが小さいものほどルートに来るようにする。
	heap := NewHeap(func(a, b Path) bool {
		return a.cost < b.cost
	})

	heap.insert(Path{node: 0, cost: 0})
	for heap.size > 0 {
		u := heap.extractMax()

		// 隣接行列を使っていた時とは違い、ヒープには
		// 同じノードへのパスが複数含まれうる。そのため既によりコストの低い
		// パスが見つかっている場合は無視する。
		if minCosts[u.node] < u.cost {
			continue
		}

		checked[u.node] = true

		for _, v := range graph[u.node] {
			cost := v.cost + u.cost
			if !checked[v.node] && cost < minCosts[v.node] {
				minCosts[v.node] = cost
				heap.insert(Path{node: v.node, cost: cost})
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range minCosts {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

// --- From ALDS1_9_C: Priority Queue

type Heap struct {
	size   int
	heap   []Path
	isHigh func(a, b Path) bool
}

func NewHeap(isHigh func(a, b Path) bool) Heap {
	heap := make([]Path, 1) // 先頭は不使用
	return Heap{size: 0, heap: heap, isHigh: isHigh}
}

func (h *Heap) insert(v Path) {
	h.size += 1
	if h.size > len(h.heap)-1 {
		h.heap = append(h.heap, v)
	} else {
		h.heap[h.size] = v
	}

	for i := h.size; i > 1; {
		parent := i / 2
		if h.isHigh(h.heap[parent], h.heap[i]) {
			break
		}
		h.heap[i], h.heap[parent] = h.heap[parent], h.heap[i]
		i = parent
	}
}

func (h *Heap) extractMax() Path {
	if h.size <= 0 {
		panic("cannot extract from empty heap")
	}

	max := h.heap[1]
	h.heap[1] = h.heap[h.size]
	h.size -= 1
	h.maxHeapify(1)

	return max
}

func (h *Heap) maxHeapify(idx int) {
	left := idx * 2
	right := left + 1
	largest := idx

	if left <= h.size {
		if h.isHigh(h.heap[left], h.heap[idx]) {
			largest = left
		}
		if right <= h.size && h.isHigh(h.heap[right], h.heap[largest]) {
			largest = right
		}
	}

	if largest != idx {
		h.heap[idx], h.heap[largest] = h.heap[largest], h.heap[idx]
		h.maxHeapify(largest)
	}
}

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];  // 重み付き有向グラフの隣接リスト表現

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;

    // 最小値を取り出し、それが最短でなければ無視
    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;
        // priority_queue はデフォルトで大きい値を優先するため -1 を掛ける
        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 <bits/stdc++.h>
using namespace std;

typedef pair<int, int> node;
typedef vector<node> Adj_list;
typedef vector<Adj_list> Adj_lists;

class less_cost{
public:
  bool operator()(const node lhs, const node rhs) const{
    return lhs.second > rhs.second;
  }
};

int main(){

  int n;
  scanf("%d", &n);

  Adj_lists adj_lists(n);

  // read weigts
  for(int i=0; i<n; i++){
    int u, k;
    scanf("%d %d", &u, &k);
    for(int j=0; j<k; j++){
      int v,c;
      scanf("%d %d", &v, &c);
      adj_lists.at(u).push_back(node(v, c));
    }
  }

  // initialize cost
  vector<int> d(n, INT_MAX);
  d.at(0) = 0;
  priority_queue<node, vector<node>, less_cost> pq;
  pq.push(node(0, d.at(0)));
  vector<bool> is_belong_to_sssp(n, false);

  //dijkstra's algorithm
  while(!pq.empty()){
    // extract node u in V-S that has minimum cost
    const node u = pq.top();
    pq.pop();

    // if u's cost is larger than d[u],
    // than ignore this one
    if(u.second > d.at(u.first)) continue;


    is_belong_to_sssp.at(u.first) = true;

    // update node in V-S and adjacent to u
    for(const node& v : adj_lists.at(u.first)){
      if(!is_belong_to_sssp.at(v.first) && d.at(u.first) + v.second < d.at(v.first)){
        d.at(v.first) = d.at(u.first) + v.second;
        pq.push(node(v.first, d.at(v.first)));
      }
    }
  }

  // output
  for(int i=0; i<n; i++){
    printf("%d %d\n", i, d.at(i));
  }

  return 0;
}

C++: #include<iostream>
using namespace std;
#include<queue>
#include<vector>
#include<string>
#include<string.h>
#include<algorithm>
bool b[2003];

#define REP(i, a) for(int i=0;i<a;i++)
	int N=(1<<20);
int main()
{
	pair<int,int> f;
	vector < pair<int,int> > A[10001];
	priority_queue < pair < int,int > > PQ;
	int min,b,a,k,m,n ,e,p[101],d[101],u,v; //u ?????????v????????¨
	bool color[10001];

	cin>>n;
	REP(i, n) {
		cin>>u>>k;
		REP(i, k) {
			cin>>a>>b;
			if(b==-1) b=N;
			A[u].push_back(make_pair(a,b));
		}
		color[i]=0;
		d[i]=N;
	}
	a=0;
	d[0]=0;
	PQ.push(make_pair(0,0));
	while(!PQ.empty()){
		f=PQ.top();
		PQ.pop();
		u=f.second;
		color[u]=1;
		REP(i,A[u].size()){
			v=A[u][i].first;
			if(color[v]==1){
			continue;
			}
				if(d[v]>A[u][i].second+d[u]){
					d[v]=A[u][i].second+d[u];
					PQ.push(make_pair(d[v]*-1,v));
				}
		}
	}
	REP(i,n){
		cout<<i<<" "<<(d[i] == N ? -1 : d[i])<<endl;
	
	}
	return 0;
}

C++: #include<cstdio>
#include<iostream>
#include<queue>
#include<algorithm>
#define Lens 10005
#define Inf 1<<22

using namespace std;
vector<pair<int, int> > adj[Lens];
int N;
char c[Lens];
int d[Lens];

void dijkstra()
{
	d[0] = 0;
	priority_queue<pair<int, int> > PQ;
	PQ.push(make_pair(0, 0));
	while (!PQ.empty())
	{
		pair<int, int> t = PQ.top();
		PQ.pop();
		int u = t.second;
		c[u] = 'b';
		if (d[u] < -t.first) continue;
		for (int i = 0; i < adj[u].size(); i++)
		{
			int tmp = adj[u][i].first;
			if (c[tmp] == 'w'&&d[tmp] > d[u] + adj[u][i].second)
			{
				d[tmp] = d[u] + adj[u][i].second;
				PQ.push(make_pair(-d[tmp],tmp));
		//		cout << tmp << "  " << d[tmp] << endl;
			}
		}

	}
}

int main()
{

	cin >> N;
	for (int i = 0; i < N; i++)
	{
		int k, n;
		cin >> k >> n;
		c[k] = 'w';
		d[k] = Inf;
		for (int j = 0; j < n; j++)
		{
			int v, tw;
			cin >> v >> tw;
			adj[k].push_back(make_pair(v, tw));
		}

	}
	dijkstra();
	for (int i = 0; i < N; i++)
	{
		cout << i << ' ' << d[i] << endl;;
	}
	return 0;
}