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)
	}
}

Python: from sys import stdin
input = stdin.readline
import heapq

infty = 2**21

def dijkstra(n):
    d = [infty] * n
    color = [0] * n

    d[0] = 0
    PQ = [(0, 0)]
    heapq.heapify(PQ)
    color[0] = 1

    while PQ:
        f = heapq.heappop(PQ)
        u = f[1]
        color[u] = 2

        #最小値を取り出し、それが最短でなければ無視
        if d[u] < f[0]:
            continue

        for adj_u in adj[u]:
            v = adj_u[0]
            if color[v] == 2:
                continue
            if d[v] > d[u] + adj_u[1]:
                d[v] = d[u] + adj_u[1]
                heapq.heappush(PQ, (d[v], v))
                color[v] = 1


    for i in range(n):
        print(str(i) + ' ' + str(-1 if d[i] == infty else d[i]))


n = int(input())

adj = [0]*n

for _ in range(n):
    u, k, *vc = map(int, input().split())
    vx_tuple = [0] * k
    for i, (v, c) in enumerate(zip(vc[::2], vc[1::2])):
        #pythonにはvectorないので、tupleで代用
        vx_tuple[i] = (v, c)
    adj[u] = vx_tuple


dijkstra(n)

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
  
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
  
using namespace std;
  
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
  
const int INF=1<<29;
const double EPS=1e-9;
  
const int dx[]={1,0,-1,0,1,1,-1,-1},dy[]={0,-1,0,1,1,-1,-1,1};

typedef pair<int,int> P;

int main() {
    int N;
    cin >> N;
    std::vector<vector<int> > G(N, vector<int>());
    std::vector<vector<int> > dist(N, vector<int>());
    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;
            G[u].push_back(v);
            dist[u].push_back(c);
        }
    }

    std::vector<int> d(N, 100000001);
    priority_queue<P, vector<P>, greater<P> > q;
    d[0] = 0;
    q.push(P(0, 0));

    while(!q.empty()) {
        P u = q.top(); q.pop();
        int v = u.second;
        if (d[v] < u.first) {
            continue;
        }
        for (int i = 0; i < G[v].size(); i++) {
            if (d[G[v][i]] > d[v] + dist[v][i]) {
                d[G[v][i]] = d[v] + dist[v][i];
                q.push(P(d[G[v][i]], G[v][i]));
            }
        }
    }

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

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

using namespace std;

#define WHITE 0
#define BLACK 2
#define GRAY 1
#define MAX 100
#define INFITY 1<<21

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

void dijkstra()
{
	priority_queue<pair<int,int> > PQ;
	int d[MAX],color[MAX],p[MAX];

	for (int i = 0; i < n; ++i)
	{
		d[i]=INFITY;
		p[i]=-1;
		color[i]=WHITE;
	}

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

	while(!PQ.empty()){

		// 把距离最小的顶点加入单源最短路径树
		pair<int,int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=BLACK;

		// 更新距离
		for (int 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;
				PQ.push(make_pair(d[v]*-1,v));
				color[v]=GRAY;
				p[v]=u;
			}
		}
	}

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

}

int main(int argc, char const *argv[])
{
	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(make_pair(v,c));
		}
	}
	dijkstra();
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int INF = 1<<20;
int n;
vector<pair<int, int> > adj[10000];
void dijkstra(){
	priority_queue<pair <int, int> > PQ;
	int color[10000];
	int d[10000];
	for(int i=0; i<n; i++){
		d[i]=INF;
		color[i]=0;
	}
	d[0]=0;
	PQ.push(make_pair(0, 0));
	color[0]=1;
	while(!PQ.empty()){
		pair<int, int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=2;
		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]==2)
				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]=1;
			}
		}
	}
	for(int i=0; i<n; i++)
		cout<<i<<" "<<(d[i]==INF ? -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));
		}
	}
	dijkstra();
	return 0;
}