Go: package main

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

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}
func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = i
	pq[j].index = j
}
func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}
func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 // for safety
	*pq = old[0 : n-1]
	return item
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

Python: from sys import maxsize
from heapq import heappop, heappush


class Node:
    WHITE = 0
    GRAY = 1
    BLACK = 2

    def __init__(self):
        self.adjs = []
        self.color = Node.WHITE
        self.dist = maxsize

    def __lt__(self, other):
        return self.dist < other.dist

    def __repr__(self):
        return "Node({},{},{})".format(self.adjs, self.color, self.dist)


def read_adj():
    n = int(input())
    nodes = [Node() for _ in range(n)]

    for i in range(n):
        u, _, *rest = [int(x) for x in input().split()]
        for i in range(0, len(rest) - 1, 2):
            nodes[u].adjs.append((rest[i], rest[i+1]))

    return nodes


def shortest_path(nodes):
    h = []

    nodes[0].dist = 0
    nodes[0].color = Node.GRAY
    heappush(h, (0, 0))

    while len(h) > 0:
        min_dist, min_node = heappop(h)

        nodes[min_node].color = Node.BLACK
        if nodes[min_node].dist < min_dist:
            continue

        for adj, c in nodes[min_node].adjs:
            if nodes[adj].color == Node.BLACK:
                continue
            if nodes[min_node].dist + c < nodes[adj].dist:
                nodes[adj].dist = nodes[min_node].dist + c
                nodes[adj].color = Node.GRAY
                heappush(h, (nodes[adj].dist, adj))


def print_dist(nodes):
    for u, n in enumerate(nodes):
        print(u, n.dist)


def main():
    nodes = read_adj()
    shortest_path(nodes)
    print_dist(nodes)


if __name__ == '__main__':
    main()

Python: import sys, itertools
f = sys.stdin

def take2(iterable):
    i = iter(iterable)
    while True:
        yield next(i), next(i)

n = int(f.readline())
adj =[[(v, c) for v, c in take2(map(int, f.readline().split()[2:]))] for _ in range(n)]
d = [100000 * 100 + 1] * n

d[0] = 0
queue ={0}
while len(queue):
    parent = queue.pop()
    for v, c in adj[parent]:
        if d[v] > d[parent] + c:
            d[v] = d[parent] + c
            queue.union([v])

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

Python: n = int(input())
G = [[-1 for i in range(n)] for j in range(n)]
d = [999999 for i in range(n)]
  
for i in range(n):
    v = input().split()
    for j in range(int(v[1])):
        G[int(v[0])][int(v[2+2*j])] = int(v[3+2*j])

flag = [0] * n
tn = [0]
d[0] = 0
for k in range(n):
    for i in range(n):
        if i in tn:
            for j in range(n):
                if G[i][j] != -1:
                    if d[j] > d[i] + G[i][j]:
                        d[j] = d[i] + G[i][j]
                    if j not in tn:
                        tn.append(j)
  
for i in range(n):
    print(str(i) + " " + str(d[i]))

Python: #coding:utf-8
n = int(input())
inf = 1000000000000000

def minHeapify(Q,i):
    H = len(Q)
    l = 2*i
    r = 2*i + 1
    if l < H and Q[l][1] < Q[i][1]:
        smallest = l
    else:
        smallest = i
    if r < H and Q[r][1] < Q[smallest][1]:
        smallest = r

    if smallest != i:
        Q[i], Q[smallest] = Q[smallest], Q[i]
        minHeapify(Q,smallest)

def buildMinHeap(Q):
    H = len(Q)
    for i in range(H // 2, -1, -1):
        minHeapify(Q,i)

def Insert(Q,key):
    v = key[0]
    Q.append([v,inf])
    lens = len(Q)
    heapIncreaseKey(Q,lens-1,key)

def heapIncreaseKey(Q,i,key):
    Q[i][1] = key[1]
    while i > 0 and Q[i // 2][1] > Q[i][1]:
        Q[i], Q[i // 2] = Q[i // 2], Q[i]
        i //= 2

def heapExtractMin(Q):
    H = len(Q)
    minv = Q[0][0]
    Q[0] = Q[H-1]
    Q.pop()
    minHeapify(Q,0)
    return minv




def dijkstra(s):
    color = ["white" for i in range(n)]
    d = [inf for i in range(n)]
    d[s] = 0
    Q = [[s,0]]
    while Q != []:
        u = heapExtractMin(Q)
        color[u] = "black"
        for vw in mtrx[u]:
            [v,w] = vw
            if color[v] != "black":
                if d[u] + w < d[v]:
                    d[v] = d[u] + w
                    color[v] = "gray"
                    Insert(Q,[v,d[v]])
    return d



mtrx = [[] for i in range(n)]
for i in range(n):
    col = list(map(int,input().split()))
    u,k = col[0], col[1]
    for j in range(k):
        [v,w] = col[2*j+2: 2*j+4]
        mtrx[u].append([v,w])



d = dijkstra(0)
for i,j in enumerate(d):
    print(i,j)