Ciclo while

Clase 23 de 33 • Curso de Programación en Swift (2019)

Ignacio Castillejo Gómez

student•

Mi MacBook Pro i7 no pudo acabar el ciclo en menos de 3 minutos 😂

import UIKit

func isPrime(n: UInt64) -> Bool {
    if n == 0 { return false }
    if n == 1 { return false }
    var found = false
    var min: UInt64 = 2 // Primer posible divisor
    let max: UInt64 = UInt64(n / 2) // Matematicamente esta demostrado que si no existe hasta n / 2 no existe divisor \LOL
    while min <= max && !found {
        found = n % min == 0
        min += 1
    }
    
    return !found
}


for n in 0...100000 {
    if isPrime(n: UInt64(n)) {
        print("\(n)", terminator: " ")
    }
}

Jesus Espino

student•

Si quieres que vaya más rápido, puedes cambiar to variable max a max=sqrt(n) 😛

Luis Abdel Rangel Castro

student•

func isPrime(n : UInt64) -> Bool {
    if n == 0 { return false }
    if n == 1 { return false }
    var found = false
    var min: UInt64 = 2 // Primer posible divisor
    let max: UInt64 = UInt64(n / 2) // Matematicamente esta demostrado que si no existe hasta n / 2 no existe divisor \LOL

    while min <= max && !found {
        found = n % min != 0
        min += 1
    }
    
    return found
}

for n in 0...1000 {
    if isPrime(n: UInt64(n)) {
        print("\(n)", terminator: " ")
    }
}

Jose Miguel Serrato Moreno

student•

let endNumber = 100
var startNumber = 2
var primeNumbers:[Int] = []
while startNumber <= 100 {
    var isPrime = true
    for idx in 2..<startNumber {
        if startNumber % idx == 0 {
            if idx != 1 && idx != startNumber {
                isPrime = false
            }
        }
    }
    if isPrime {
        primeNumbers.append(startNumber)
    }
    startNumber += 1
}

Hugo Andres Martinez

student•

me gusto tu codigo, nada mas me podrias explicar la parte del

for idx in 2..<startNumber{} es que no comprendo porque se supone que sera del 2 hasta el start number, y el startnumber = 2. Podrias explicarme esa parte por favor

Diego Mojarro

student•

let ini = 2
let fin = 100
var prime : [Int] = []

for i in ini...fin {
    var isPrime = true
    for j in ini..<i {
        if i % j == 0{
            isPrime = false
        }
    }
    if isPrime{
        prime.append(i)
    }
}

Gera Meraki

student•

Les dejo la información a continuación, vale la pena darnos una vuelta y leer esto 😱

https://es.wikipedia.org/wiki/Criba_de_Erat%C3%B3stenes

Pedro Alejandro Montaño Herrera

student•

Jessica Balanta Restrepo

student•

Reto:

var contador = 0 while contador <= 10 { contador += 1 } print(contador)

repeat{ contador += 1 }while contador <= 0 print(contador)

//ejercicio tomar un numero del 2 al 100 y localizar el numero primo.

let numerPrime = 100 var startNumber = 2 var primeNumers:[Int] = [] while startNumber <= 100 { var isPrime = true for divisor in 2..<startNumber { if startNumber % divisor == 0{ if divisor != 1 && divisor != startNumber { isPrime = false } } } if isPrime {

primeNumers.append(startNumber)
}
startNumber += 1

} print(primeNumers)

Fabián Recuero

student•

Mi solución

var numStart = 2
var mult = 1
var count = 0
while numStart <= 100 {
    while mult <= numStart {
        if (numStart % mult) == 0 {
            count += 1
        }
        mult += 1
    }
    if count <= 2 {
        print("\(numStart) es un número primo")
    }
    numStart += 1
    mult = 1
    count = 0
}

Wilson Montenegro

student•

// Reto
var numbers = Set<Int>()
var criba = Set<Int>()

for totalNumbers in 1...100 {
    numbers.insert(totalNumbers)
}
criba.insert(1)
for multiplesOf2 in stride(from: 4, to: 101, by: 2){
    criba.insert(multiplesOf2)
}
for multiplesOf3 in stride(from: 6, to: 101, by: 3){
    criba.insert(multiplesOf3)
}
for multiplesOf5 in stride(from: 10, to: 101, by: 5){
    criba.insert(multiplesOf5)
}
for multiplesOf7 in stride(from: 14, to: 101, by: 7){
    criba.insert(multiplesOf7)
}

let primeNumbers = numbers.symmetricDifference(criba).sorted()
print(primeNumbers)

Juan Sebastián Vargas Castañeda

student•

Naive Algorithm

//Ejercicio - Número primos del 2 al 100
let n = 100
var number = 2 //From number to 100
var div = 2 //First prime number, first divisor for all numbers from now on.

while number <= n
{
    var isPrime = true //Let's assume number is always prime until we demonstrate the opposite
    while (isPrime) && (number != div)
    {
        isPrime = ( number % div != 0 )
        div += 1
    }
    div = 2 //Reset div to 2 to iterate for the next loop
    if isPrime
    {
        print(number, separator: "", terminator: " ") //Wanna know which ones are primes
    }
    number += 1 //Next number
}
//OUTPUT:2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

Luis Martin Maceda

student•

var min = 2
var max = 100
var noPrimos = Set<Int>()
print("Los numeros primos en el rango 2 a 100: ", terminator: " ")
while min < max {
    for aux in (min+1)...max {
        if aux%min == 0 {
            noPrimos.insert(aux)
        }
    }
    if !noPrimos.contains(min) {
        print("\(min),", terminator: " ")
    }
    min += 1
}

Francisco Guadalupe Roque Reyes

student•

repeat{

num += 1

res = num % 2

if res != 0{

res = num % 3

if res != 0{

res = num % 5

if res != 0{

res = num % 7

if res != 0{