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<cstdio>
#include<climits>
using namespace std;
 
#define N 9000
int n;
 
int g[N][N];
 
int weight[N];
bool us[N];
 
//prim
void prim(){
 
  int v;
  
  weight[0]=0;
   
  while(true){
    v=-1;
    
    for(int i=0;i<n;i++){
      if(us[i]!=true && (v==-1 ||weight[i]<weight[v]))v=i;
    }
 
    if(v==-1)break;
    us[v]=true;
  
 
    for(int i=0;i<n;i++){
      if(weight[i]>(g[v][i]+weight[v])){
 
        weight[i]=(g[v][i]+weight[v]);
        //      cout <<"fsafa"<<endl;
      }
    }
  }
  
}
 
 
int main(){
 
  int u,k1,c,v;
 
  for(int i=0;i<N;i++){
    for(int j=0;j<N;j++){
      g[i][j]=9953535;
    }
  }
 
  //load n
  cin >>n;
 
  //load data
  for(int i=0;i<n;i++){
    weight[i]=INT_MAX;
    us[i]=false;
    scanf("%d %d",&u,&k1);
    for(int j=0;j<k1;j++){
      scanf("%d %d",&v,&c);
      g[u][v]=c;
      //    cout <<g[i][j]<<" ";
    }
    //    cout <<endl;
  }
 
 
 
 
  //print
  prim();
 
  for(int i=0;i<n;i++){
    cout <<i<<" "<<weight[i]<<endl;
  }
  return 0;
 
}

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

static const int MAX = 10000;
static const int INF = (1<<21);
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(){
    int color[MAX], d[MAX];

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

    d[0] = 0;

    // pair<vに到達するまでのスコア、v>
    priority_queue<pair<int,int>> pq;
    pq.push({0,0});

    while(!pq.empty()){
        pair<int,int> p = pq.top(); pq.pop();
        int u = p.second;
        
        color[u] = BLACK;
        if(d[u] < p.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][v].second){
                d[v] = d[u] + adj[u][v].second;
                pq.push((-1)*d[v], v);
                color[v] = GRAY;
            }
        }
    }

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

int main(){
   int u, k, 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({v,c});
       }
   }

   dijkstra();

   return 0;
}

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

class blanch{
	public:
		bool visited;
		int distance;
		int from;
		int to;
};
typedef vector <blanch> vb;
typedef vector <vb> vvb;

int make_graph(vvb &graph, vb &nodes){

	int n=nodes.size();
	for (int i=0; i<n; i++){
		nodes[i].visited = false;
		nodes[i].distance = INT_MAX;
	}

	for (int i=0; i<n; i++){
		int i2, n2;
		cin>>i2;
		cin>>n2;

		blanch tmp;
		tmp.visited = false;
		tmp.from = i2;

		for (int j=0; j<n2; j++){
			cin>>tmp.to;
			cin>>tmp.distance;
			graph[i2].push_back(tmp);
		}
	}
	return 0;
}

int Shortest_Path(vvb &graph, vb &nodes){

	int p1=0;
	nodes[p1].distance = 0;

	int p2;
	while (p1 != -1){
		nodes[p1].visited=true;
		for (int i = 0; i < (int)graph[p1].size(); i++){
			blanch tmp = graph[p1][i];
			p2=tmp.to;
			if (!nodes[p2].visited){
				int tmp2 = tmp.distance + nodes[p1].distance;
				if (tmp2 < nodes[p2].distance){
					tmp.distance = tmp2;
					nodes[p2] = tmp;
				}
			}
		}

		p1 = -1;
		int tmp = INT_MAX;
		for (int i=0; i<(int)graph.size(); i++){
			if (!nodes[i].visited && nodes[i].distance<tmp){
				p1 = i;
				tmp = nodes[i].distance;
			}
		}
	}
	return 0;
}

int resultout(vb &nodes){
	for (int i=0; i<(int)nodes.size(); i++){
		cout<<i<<" "<<nodes[i].distance<<endl;
	}
	return 0;
}

int main(void){

	int n;
	cin>>n;
	vvb G(n, vb());
	vb nodes(n);

	make_graph(G, nodes);

	Shortest_Path(G, nodes);

	resultout(nodes);
	G.clear();
	nodes.clear();

	return 0;
}