ooade

raw_input()
m = raw_input()
w = raw_input()

w = [float(i) for i in w.split()]
m = sum([w[int(i)] * int(j) for i, j in enumerate(m.split())])

print "%.1f" % (m / sum(w))

ooade

class BankAccount():
	def withdraw():
		pass
	def deposit():
		pass
	
class SavingsAccount(BankAccount):
	def __init__(self):
		self.balance = 500
	

ooade

def replicate_recur(times, data):
	try:
		if type(data) is not(int) and type(data) is not(str):
			raise ValueError("Wrong Input Found!")
		arr = [] 
		def recur(times, data):
			if times <= 0:
				return arr
		  	else:
			  	arr.append(data)

ooade

def manipulate_data(lst):
	
  if type(lst) is not(list):
  	print type(lst)
  	return "Only lists allowed"
    
  negatives = sum(filter(lambda x: x < 0, lst))
  positives = len(filter(lambda x: x > -1, lst))
  
  return [positives, negatives]

ooade

function main() {
    let N = readLine()
    let S = N.match(/.{1,3}/g);
    let R = 'SOS'.repeat(N.length / 3).match(/.{1,3}/g);
        
    let count = 0;
    
    for (let i in S) {
        for (let j in S[i]) {
         if (S[i][j] !== R[i][j]) {

ooade

function main() {
    let S = readLine().match(/.{1,3}/g);
    
    let count = 0;
    
    for (let i in S) {
        if (S[i][0] !== 'S') {
            count++;
        }
        

ooade

const log = (...args) => args.map(arg => console.log(arg)); // Pollyfill for Logging each args on a new line

function processData(input) {
    let ARR = input.split('\n');
    ARR.shift();
    ARR = ARR.join().split(' ').map(Number).sort((a, b) => a - b);
    
    let Q1a = []; // First Quartile Array
    let Q3a = []; // Third Quartile Array
    

ooade

function main() {
    var n_temp = readLine().split(' ');
    var n = parseInt(n_temp[0]);
    var k = parseInt(n_temp[1]);
    a = readLine().split(' ');
    a = a.map(Number);
    
    var i = k;
    
    if (k > n) {

ooade

const express = require('express');
// Chalk was added by create-react-app, use only on the dev side
const chalk = require('chalk');

// Initialize express
const app = express();
const PORT = process.env.PORT || 3000;

// Start up our express server
app.listen(PORT, (error) => {

ooade

{
  "name": "express-without-eject",
  "version": "0.1.0",
  "private": true,
  "devDependencies": {
    "react-scripts": "0.7.0"
  },
  "dependencies": {
    "express": "^4.14.0"
  },