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>
using namespace std;
static const int maxs=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[maxs][maxs];

void dicstra(){
  int minv;
  int d[maxs],color[maxs];
  for(int i=0;i<n;i++){
    d[i]=infty;
    color[i]=white;
  }
  d[0]=0;
  color[0]=gray;
  while(1){
    minv=infty;
    int u=-1;
    for(int i=0;i<n;i++){
      if(minv>d[i]&&color[i]!=black){
	u=i;
	minv=d[i];
      }
    }
    if(u==-1)break;
    color[u]=black;
    for(int v=0;v<n;v++){
      if(color[v]!=black&&m[u][v]!=infty){
	if(d[v]>d[u]+m[u][v]){
	  d[v]=d[u]+m[u][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<k;j++){
      cin>>v>>c;
      m[u][v]=c;
    }
  }
  dicstra();
  return 0;
}

C++: #include <vector>
#include <queue>
#include <cstdio>
#include <utility>
#include <climits>

int main(){
	std::priority_queue<std::pair<int, int>> queue;
	int n;
	std::scanf("%d", &n);
	std::vector<std::vector<std::pair<int, int>>> edges;
	std::vector<int> result(n, INT_MAX);
	for (auto i = 0; i < n; ++i){
		std::vector<std::pair<int, int>> edge;
		int u, k;
		std::scanf("%d %d", &u, &k);
		for (auto j = 0; j < k; ++j){
			int c, v;
			std::scanf("%d %d", &v, &c);
			edge.push_back(std::make_pair(v, c));
		}
		edges.push_back(edge);
	}
	queue.push(std::make_pair(0, 0));
	for (auto i = 0; i < n; ++i){
		while (result.at(queue.top().second) < -queue.top().first){
			//std::cout << queue.top().second << "qqqq" << queue.top().first << std::endl;
			queue.pop();
		}
		int dist = -queue.top().first; int vert = queue.top().second;
		queue.pop();
		result.at(vert) = dist;
		//std::cout << vert << "v-d" << dist << std::endl;
		for (auto j : edges.at(vert)){
			//std::cout << j.first << "(" << result.at(j.first) << ")" << "||" << j.second << "\n";
			if (result.at(j.first) > dist+ j.second){
				queue.push(std::make_pair(-dist - j.second, j.first));
				result.at(j.first) = dist + j.second;
			}
		}
	}
	for (auto i = 0; i < n; ++i){
		std::printf("%d %d\n", i, result.at(i));
	}
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX=10000;
static const int I=(1<<20);
static const int W=0;
static const int G=1;
static const int B=2;

int n;
vector<pair<int,int> > adj[MAX];

void di(){
  priority_queue<pair<int,int> > PQ;
  int color[MAX];
  int d[MAX];
  for(int i=0;i<n;i++){
    d[i]=I;
    color[i]=W;
  }


  d[0]=0;
  PQ.push(make_pair(0,0));
  color[0]=G;

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

    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]==B) 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]=G;
      }
    }
  }


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

  di();

  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
//template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
//template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }

const int INF = 1<<20;

int n;
vector<pair<int, int>> adj[10005];


void dijkstra(){
    priority_queue<pair<int, int>> PQ;
    bool visited[n];
    int d[n];

    for(int i=0; i<n; i++){
        visited[i] = false;
        d[i] = INF;
    }

    PQ.push({0, 0});
    d[0] = 0;

    while(!PQ.empty()){

        pair<int, int> p = PQ.top(); PQ.pop();
        int u = p.second;

        visited[u] = true;

        if(d[u] < p.first * (-1)) continue;
        
        for(int i=0; i<adj[u].size(); i++){
            int v = adj[u][i].first;
            if(visited[v] == false && d[v] > d[u] + adj[u][i].second){
                d[v] = d[u] + adj[u][i].second;
                PQ.push({d[v] * (-1), v});
            }
        }
    }

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

}

int main(void){
    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;
            adj[u].push_back(make_pair(v, c));
        }
    }

    dijkstra();
}