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: inf = float('inf')
n = int(input())
g = []
for i in range(n):
    line = list(map(int, input().split()[2:]))
    g.append(zip(line[0::2], line[1::2]))

distance = [inf] * n
distance[0] = 0
visited = [False] * n
current = 0

while not all(visited):
    visited[current] = True
    for v, c in g[current]:
        if not visited[v] and distance[current] + c < distance[v]:
            distance[v] = distance[current] + c
    min_i = 0
    min_d = inf
    for i in range(n):
        if not visited[i] and distance[i] < min_d:
            min_i = i
            min_d = distance[i]
    current = min_i

for i in range(n):
    print(i, distance[i])

Python: N = int(input())
G = [[] for i in range(N)]
for nod in range(N):
    tmp = list(map(int, input().split()))
    for i in range(2, tmp[1]*2+1, 2):
        edge, cos = tmp[i], tmp[i+1]
        G[nod].append([edge, cos])



import heapq


def dijkstra(x):
    d = [float('inf')] * N
    d[x] = 0
    visited = {x}

    # d, u
    hq = [(0, x)]

    while hq:
        u = heapq.heappop(hq)[1]
        visited.add(u)

        for node, cost in G[u]:
            if (node not in visited) and d[node] > d[u] + cost:
                d[node] = d[u] + cost
                heapq.heappush(hq, (d[u]+cost, node))
    return d


distance = dijkstra(0)
#print(distance)
for i in range(N):
    print(i, distance[i])

N = int(input())
G = [[] for i in range(N)]
for nod in range(N):
    tmp = list(map(int, input().split()))
    for i in range(2, tmp[1]*2+1, 2):
        edge, cos = tmp[i], tmp[i+1]
        G[nod].append([edge, cos])



import heapq


def dijkstra(x):
    d = [float('inf')] * N
    d[x] = 0
    visited = {x}

    # d, u
    hq = [(0, x)]

    while hq:
        u = heapq.heappop(hq)[1]
        visited.add(u)

        for node, cost in G[u]:
            if (node not in visited) and d[node] > d[u] + cost:
                d[node] = d[u] + cost
                heapq.heappush(hq, (d[u]+cost, node))
    return d


distance = dijkstra(0)
#print(distance)
for i in range(N):
    print(i, distance[i])

Python: import sys

f_i = sys.stdin

n = int(f_i.readline())

adj = [[(int(cost), int(v_n)) for v_n, cost in zip(x.split()[2::2], x.split()[3::2])] for x in f_i]

import heapq

def dijkstra():
    PQ = [(0, 0)]
    isVisited = [False] * n
    distance = [999900001] * n

    distance[0] = 0
    
    while PQ:
        uc = heapq.heappop(PQ)
        u = uc[1]

        if uc[0] > distance[u]:
            continue

        isVisited[u] = True
        
        for vc in adj[u]:
            v = vc[1]
            if isVisited[v] == True:
                continue
            t_cost = distance[u] + vc[0]
            if t_cost < distance[v]:
                distance[v] = t_cost
                heapq.heappush(PQ, (t_cost, v))

    for v, d in enumerate(distance):
        print(v, d)


dijkstra()

Python: # coding: utf-8
# Your code here!
import heapq

WHITE = 0
GRAY = 1
BLACK = 2

INF = 2000000000


def dijkstra():
    PQ = []
    heapq.heapify(PQ)
    color = [WHITE] * n
    d = [INF] * n
    
    d[0] = 0
    heapq.heappush(PQ, (0, 0))
    color[0] = GRAY
    
    while len(PQ) != 0:
        
        f = heapq.heappop(PQ)
        u = f[1]
        color[u] = BLACK
        
        if d[u] < f[0]:
            continue
        
        for j in range(len(adj[u])):
            v = adj[u][j][0]
            if color[v] == BLACK:
                continue
            if d[v] > d[u] + adj[u][j][1]:
                d[v] = d[u] + adj[u][j][1]
                heapq.heappush(PQ, (d[v], v))
                color[v] = GRAY
    for i in range(n):
        print(i, d[i])


n = int(input())

adj = [[] for j in range(n)]
for i in range(n):
    nums=list(map(int,input().split()))
    for j in range(nums[1]):
        adj[nums[0]].append((nums[2*j+2], nums[2*j+3]))
        

dijkstra()

Python: N = int(input())

E = [None] * N
for _ in range(N):
    u, k, *vs = map(int, input().split())
    E[u] = []
    for i in range(k):
        v, c = vs[i*2], vs[i*2+1]
        E[u].append((v, c))

import heapq

vis = [False] * N
inf = 1e9
d = [inf] * N
d[0] = 0
pq = [(0, 0)]
while pq:
    nv, ni = heapq.heappop(pq)
    if nv > d[ni]:
        continue
    d[ni] = nv
    vis[ni] = True
    for v, c in E[ni]:
        nc = d[ni] + c
        if not vis[v] and nc < d[v]:
            heapq.heappush(pq, (nc, v))

for v in range(N):
    print(v, d[v])