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++: /*
 * c.cc: 
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>

using namespace std;

/* constant */

const int MAX_N = 10000;
const int INF = 1 << 30;

/* typedef */

typedef pair<int,int> pii;
typedef vector<pii> vpii;

/* global variables */

vpii nbrs[MAX_N];
int dists[MAX_N];

/* subroutines */

/* main */

int main() {
  int n;
  cin >> n;

  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;
      nbrs[u].push_back(pii(v, c));
    }
  }

  for (int i = 0; i < n; i++) dists[i] = INF;
  dists[0] = 0;

  priority_queue<pii> q;
  q.push(pii(0, 0));

  while (! q.empty()) {
    pii u = q.top(); q.pop();
    int ud = -u.first, &ui = u.second;
    if (dists[ui] != ud) continue;

    vpii& nbru = nbrs[ui];
    for (vpii::iterator vit = nbru.begin(); vit != nbru.end(); vit++) {
      int &vi = vit->first, vd = ud + vit->second;
      if (dists[vi] > vd) {
	dists[vi] = vd;
	q.push(pii(-vd, vi));
      }
    }
  }

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

  return 0;
}

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

#define N 10000
#define INFTY (1 << 21)
#define WHITE 0
#define GRAY 1
#define BLACK 2

int n;
int d[N], color[N], p[N];
vector<pair<int, int> > adj[N];
priority_queue<pair<int, int> > PQ;

void dijkstra(int s){
  for(int i = 0 ; i < n ; i++){
    color[i] = WHITE;
    d[i] = INFTY;
    p[i] = -1;
  }
  d[s] = 0;
  PQ.push(make_pair(d[s], s));
  color[s] = 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])<<"\n";
  }
}

int main(){
  cin >> n;
  for(int i = 0 ; i < n ; i++){
    int u, k, v, c;
    cin >> u >> k;
    for(int j = 0; j < k ; j++){
      cin >> v >> c;
      adj[u].push_back(make_pair(v, c));
    }
  }
  dijkstra(0);
}

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

int x[10000][10000];
int y[10000];

int main() {
	memset(x, 1, sizeof(x));
	memset(y, 1, sizeof(y));
	int n, a, b, c, d;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> a >> b;
		for (int i = 0; i < b; i++) {
			cin >> c >> d;
			x[a][c] = d;
		}
	}
	y[0] = 0;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			for (int k = 0; k < n; k++) {
				y[k] = min(y[k], y[j] + x[j][k]);
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << ' ' << y[i] << endl;
	}
	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
#define pb push_back
#define fi first
#define se second

#define MAX_V 10101
#define INF 1e9

struct edge{int to,cost;};
typedef pair<int,int> P;
int d[MAX_V];
int V;
vector<edge> G[MAX_V];

edge makeedge(int t,int c){
    edge e;
    e.to=t;
    e.cost=c;
    return e;
}

void addedge(int s,int t,int c){
    G[s].push_back(makeedge(t,c));
    //G[t].push_back(makeedge(s,cost));
}

void dijkstra(int s){
    priority_queue<P, vector<P>, greater<P> > que;
    fill(d,d+V,INF);
    d[s]=0;
    que.push(P(0,s)); 

    while(!que.empty()){
        P p=que.top(); que.pop();
        int v=p.second;
        if(d[v]<p.first) continue;
        for(int i=0;i<G[v].size();i++){
            edge &e=G[v][i];
            if(d[e.to]>d[v]+e.cost){
                d[e.to]=d[v]+e.cost;
                que.push(P(d[e.to],e.to));
            }
        }
    }
}


int main(){
    int i,j,n;
    cin>>n;
    V=n;
    int u,k;
    int x,y;
    for(i=0;i<n;i++){
        cin>>u>>k;
        for(j=0;j<k;j++){
            cin>>x>>y;
            addedge(i,x,y);
        }
    }
    dijkstra(0);
    for(i=0;i<n;i++){
        cout<<i<<" "<<d[i]<<endl;
    }
    return 0;
}