Swift - 12 - 区间运算符和for-in
//: Playground - noun: a place where people can play import UIKit var str = "Hello, playground" var a = 1, b = 10 // a到b(包含a,b) [a,b] a...b // a到b-1(包含a,不包含b) [a,b) a..<b // for-in循环 for index in a..<b { // index为常量 index } var array = ["Rinpe", "Bobo", "Lala"] for index in 0...(array.count - 1) { array[index] }