Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
const INF = 1 << 60

type Edge struct {
	to, cost int
}

type Node struct {
	id, cost int
}

type PQ []Node

func (pq PQ) Len() int           { return len(pq) }
func (pq PQ) Less(i, j int) bool { return pq[i].cost < pq[j].cost }
func (pq PQ) Swap(i, j int)      { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PQ) Push(x interface{}) {
	*pq = append(*pq, x.(Node))
}

func (pq *PQ) Pop() interface{} {
	old := *pq
	n := len(old)
	x := old[n-1]
	*pq = old[0 : n-1]
	return x
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		E[id] = make([]Edge, k)
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id][j] = Edge{to, cost}
		}
	}

	d := make([]int, N)
	for i := 0; i < N; i++ {
		d[i] = INF
	}
	done := make([]bool, N)
	pq := &PQ{}
	heap.Init(pq)
	d[0] = 0
	heap.Push(pq, Node{0, 0})
	for pq.Len() > 0 {
		cur := heap.Pop(pq).(Node).id
		if done[cur] {
			continue
		}
		done[cur] = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+d[cur]
			if !done[to] && cost < d[to] {
				d[to] = cost
				heap.Push(pq, Node{to, cost})
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, d[i])
	}
	wtr.Flush()
}

Python: import sys
readline = sys.stdin.readline
from heapq import heapify, heappush, heappop
INF = float("inf")
def MAIN():
    n = int(input())
    adj = [[]] * n
    for _ in range(0, n):
        U = list(map(int, readline().split()))
        adj[U[0]] = zip(U[2::2], U[3::2])
    def dijkstra():
        d = [0] + [INF] * (n - 1)
        hq = [(0, 0)]
        while hq:
            u = heappop(hq)[1]
            for v, c in adj[u]:
                alt = d[u] + c
                if d[v] > alt:
                    d[v] = alt
                    heappush(hq, (alt, v))
        print("\n".join(f"{i} {c}" for i, c in enumerate(d)))
    dijkstra()
MAIN()

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;
}