Go: package main

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

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
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 = j
	pq[j].index = i
}

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
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist *[][]int, n int) *[]int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range (*dist)[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return &shortests
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(&dist, n)
	for i, d := range *shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

Python: class RadixHeap:
    __slots__ = ["data", "last", "siz", "used"]

    # (max_key - min_key) <= C
    def __init__(self, N, C):
        self.data = [[] for i in range(C.bit_length() + 1)]
        self.last = self.siz = 0
        self.used = [0]*N

    def push(self, x, key):
        #assert self.last <= x
        self.siz += 1
        self.data[(x ^ self.last).bit_length()].append((x, key))

    def pop(self):
        data = self.data
        used = self.used
        #assert self.siz > 0
        if not data[0]:
            i = 1
            while not data[i]:
                i += 1
            d = data[i]
            new_last, new_key = min(d)
            used[new_key] = 1
            for val in d:
                x, key = val
                if used[key]:
                    self.siz -= 1
                    continue
                data[(x ^ new_last).bit_length()].append(val)
            self.last = new_last
            data[i] = []
        else:
            new_last, new_key = data[0].pop()
            used[new_key] = 1
            self.siz -= 1
        return new_last, new_key

    def __len__(self):
        return self.siz

import sys
readline = sys.stdin.readline
write = sys.stdout.write


N = int(readline())
G = [None] * N
for i in range(N):
    u, k, *V = map(int, readline().split())
    G[i] = [(v, c) for v, c in zip(V[::2], V[1::2])]

def dijkstra(N, G, s):
    que = RadixHeap(N, 10**9 + 1)

    dist = [10**18]*N
    dist[s] = 0
    que.push(0, s)
    while que:
        cost, v = que.pop()
        if dist[v] < cost:
            continue
        for w, c in G[v]:
            if cost + c < dist[w]:
                dist[w] = r = cost + c
                que.push(r, w)
    return dist
dist = dijkstra(N, G, 0)
write("\n".join("%d %d" % (i, d) for i, d in enumerate(dist)))
write("\n")

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_node, min_dist = heappop(h)
        if nodes[min_node].dist < min_dist:
            continue

        nodes[min_node].color = Node.BLACK

        for adj, c in nodes[min_node].adjs:
            if nodes[min_node].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, (adj, nodes[adj].dist))


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: n = int(input())
from collections import defaultdict
G = defaultdict(list)
for i in range(n):
    i = [int(i) for i in input().split()]
    k = i[1]
    G[i[0]] = list(zip(i[2::2],i[3::2]))

def mind(Q, d):
    c = float('inf')
    ret = 0
    for i, j in enumerate(d):
        if c > j and i in Q:
            c = j
            ret = i
    return ret

def dijkstra(G):
    d = [0] + [float('inf')] * (n - 1)
    Q = set(range(n))
    while len(Q) != 0:
        u = mind(Q, d)
        Q = Q - set([u])
        for v, c in G[u]:
            if d[v] > d[u] + c:
                d[v] = d[u] + c
    return d

for i,j in enumerate(dijkstra(G)):
    print(i, j)