const numbers = [0, 1, 2, 3, 4, 5, 6, 7]

const doubleNumbers = numbers.map(function(n) {
    return (n * 2)
})

console.log(doubleNumbers)      // (7) [0, 2, 4, 6, 8, 10, 12]

const numbers = [0, 1, 2, 3, 4, 5, 6, 7]
const doubleNumbers = numbers.map(n => n * 2)

console.log(doubleNumbers)     //(7) [0, 2, 4, 6, 8, 10, 12]

const doubleNumbers = numbers.map((n) => {
    return n * 2
})

console.log(doubleNumbers)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const oddOrEven = numbers.map(function(a,b) {
    return a % 2 === 0 ? b + ' parzysta' : b + ' nieparzysta'
})

console.log(oddOrEven)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const oddOrEven = numbers.map((a,b) =>
    a % 2 === 0 ? b + ' parzysta' : b + ' nieparzysta'
)

console.log(oddOrEven)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const oddOrEven = numbers.map((a,b) => {
    return a % 2 === 0 ? b + ' parzysta' : b + ' nieparzysta'
})

console.log(oddOrEven)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const evenNumbers = numbers.filter((a,b) =>
    a % 2 === 0
)

console.log(evenNumbers)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const evenNumbers = numbers.filter(function(a,b) {
    return a % 2 === 0
})

console.log(evenNumbers)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const sum = numbers.reduce((acc, next) => {
    return acc+ next
}, 10)

console.log(sum)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const sum = numbers.reduce((acc, next) =>
    acc+ next
, 20)

console.log(sum)

const numbers = [0, 1, 2, 3, 4, 5, 6]

const getStringWithNumbers = numbers.join()

console.log(getStringWithNumbers) //0,1,2,3,4,5,6