swift filter関数、reduce関数、MinMax関数の使い方

fileter

let numarray = [1,2,3,4,5]
let newnumArray = numarray.filter { $0 < 3 } // 2までの値をフィルタリングする
print(newnumArray)

//出力結果
[1, 2]

reduce

let reduceArray = [1,2,3,4,5]
var total = reduceArray.reduce(0) { (num1, num2) -> Int in
    return num1 + num2
}
print(total)

//出力結果
15

reduce もっと短く書く

let reduceArray = [1,2,3,4,5]
let total1 = reduceArray.reduce(0, +) //　たしざん
let total2 = reduceArray.reduce(1, *) // かけざん

print(total1)　//15
print(total2) //120

関数でMin、Maxを取得

let scores = [84, 76, 91, 62 ,80]
let min = scores.min()
let max = scores.max()
print(min) // 62
print(max) // 91