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 <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 pair<int, int> lhs, const pair<int, int> 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)));

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

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

    // update node in V-S and adjacent to u
    for(const node& v : adj_lists.at(u.first)){
      if(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)));
      }
    }

    pq.pop();
  }

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

  return 0;
}

C++: #include <stdio.h>
#include <cmath>
#include <algorithm>
#include <stack>
#include <queue>
#include <vector>
typedef long long int ll;

#define BIG_NUM 2000000000

using namespace std;

struct Node{

	Node(int arg_to,int arg_cost){
		to = arg_to;
		cost = arg_cost;
	}
	bool operator<(const struct Node &arg) const{
			return cost > arg.cost;
	};

	int to,cost;
};

int main(){

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

	vector<Node> V[N];

	int node,num,to,cost,D[N];;

	for(int loop = 0; loop < N; loop++){
		scanf("%d",&node);
		scanf("%d",&num);
		for(int i = 0; i < num; i++){
			scanf("%d %d",&to,&cost);
			V[node].push_back(Node(to,cost));
		}
		D[loop] = BIG_NUM;
	}

	D[0] = 0;

	priority_queue<Node> Q;

	for(int i = 0; i < V[0].size(); i++){
		D[V[0][i].to] = V[0][i].cost;
		Q.push(Node(V[0][i].to,V[0][i].cost));
	}

	int min_index;

	while(!Q.empty()){
		if(Q.top().cost == D[Q.top().to]){
			min_index = Q.top().to;
			Q.pop();
		}else{
			Q.pop();
			continue;
		}

		for(int k = 0; k < V[min_index].size(); k++){
			if(D[V[min_index][k].to] > D[min_index] + V[min_index][k].cost){
				D[V[min_index][k].to] = D[min_index] + V[min_index][k].cost;
				Q.push(Node(V[min_index][k].to,D[V[min_index][k].to]));
			}
		}
	}

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

    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

int cost[10000][10000];//cost[a][b] a??????b????§?????????????????????????
long long int d[10000];//??????s?????????????°??????¢
bool used[10000];
int arrow;//????????°

const int INF = 10000000;

void dijkstra(){
  fill(d,d+arrow,INF);
  fill(used,used + arrow,false);
  d[0] = 0;

  while(1){
    int v=-1;
    // ???????????????????????????????????????????????¢???????°???????????????¢???
    for(int u=0;u<arrow;u++){
      if(!used[u] && (v == -1 || d[u] < d[v])) v = u;
    }

    if(v == -1) break;

    used[v] = true;

    for(int u=0; u<arrow; u++){
      if(cost[v][u] != INF){
        d[u] = min(d[u],d[v] + cost[v][u]);
      }
    }
  }

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

}

int main(){

    cin >> arrow;

    int n,a,v,c;



    for(int i=0;i<arrow;i++){
      for(int j=0;j<arrow;j++){
        cost[i][j] = INF;
      }
    }

    for(int u=0;u<arrow;u++){

      cin >> n >> a;

      for(int i=0; i<a;i++){
        cin >> v >> c;
        cost[n][v] = c;
      }
    }

    dijkstra();

    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>

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;

void dijkstra(int n, std::vector<std::pair<int, int> > adj[MAX]) {
	std::priority_queue<std::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(std::make_pair(0, 0));
	color[0] = GRAY;

	while (!PQ.empty()){
		std::pair<int, int> f = PQ.top(); PQ.pop();
		int u = f.second;
		color[u] = BLACK;

		//????°???????????????????????????????????????§???????????°??????
		if (d[u] < f.first * (-1))continue;
		
		for (size_t i = 0; i < adj[u].size(); i++) {
			int v = adj[u][i].first;
			if (color[v] == BLACK) continue;
			if (d[v] > d[u] + adj[u][i].second) {
				d[v] = d[u] + adj[u][i].second;
				//priority_queue????????????????????§??§??????????????????????????????-1????????????
				PQ.push(std::make_pair(d[v] * -1, v));
				color[v] = GRAY;
			}
		}
	}

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

int main() {
	std::vector<std::pair<int, int> > adj[MAX];
	int n;

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

	dijkstra(n, adj);
	
	return 0;
}