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;
static const int MAX = 10000;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;
static const int INFTY = (1<<20);
int n;
vector<pair<int,int> >adj[MAX];


void dijkstra(){
    priority_queue<pair<int,int> >PQ;
    int color[MAX],d[MAX];
    
    for (int i = 0; i < n; i++)
    {
        color[i] = WHITE;
        d[i] = INFTY;
        
    }
    d[0] = 0;color[0] = GRAY;
    PQ.push(make_pair(0,0));

    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;
                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(){
    cin >> n;
    int u,k,c,v;
    
    
    
    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 <cstdio>
#include <algorithm>
#include <queue>
using namespace std;

// first: cost, second: key
typedef pair<int, int> vert;

static const int MAX   = 10000;
static const int INFTY = 1 << 20;
static const int WHITE = 0;
static const int BLACK = 2;

vector<vert> adjs[MAX];

void dijkstra(int n_v, int v_start) {
    priority_queue< vert, vector<vert>, greater<vert> > visitings;
    int color[MAX];
    int costs[MAX];

    for (int i = 0; i < n_v; i++) {
        costs[i] = INFTY;
        color[i] = WHITE;
    }

    costs[v_start] = 0;
    visitings.push( make_pair(0, v_start) );

    while (! visitings.empty()) {
        vert nearest = visitings.top();
        visitings.pop();

        int next_id = nearest.second;
        color[next_id] = BLACK;

        if ( costs[next_id] < nearest.first )
            continue;

        for (int i = 0; i < adjs[next_id].size(); i++) {
            int adj  = adjs[next_id][i].first;
            int cost = adjs[next_id][i].second;

            if (color[adj] == BLACK)
                continue;

            if (costs[next_id] + cost < costs[adj]) {
                costs[adj] = costs[next_id] + cost;
                visitings.push( make_pair(costs[adj], adj) );
            }
        }
    }

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

int main() {
    int n_v;
    scanf("%d", &n_v);

    for (int i = 0; i < n_v; i++) {
        int vert_id, n_adjs;
        scanf("%d %d", &vert_id, &n_adjs);

        for (int j = 0; j < n_adjs; j++) {
            int adj, cost;
            scanf("%d %d", &adj, &cost);
            adjs[vert_id].push_back( make_pair(adj, cost) );
        }
    }

    dijkstra(n_v, 0);
}

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];

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;
        
        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]) << endl;
    }
}

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