赋值运算符
import UIKit
// 赋值运算符
let a = 10
var b = 5
b = a
print(b)
算数运算符
// 算数运算符
1 + 2
5 - 3
2 * 3
10.0 / 2.5
取余运算符
// 取余运算符
10 % 4
比较运算符
// 比较运算符
// 相等
1 == 1
// 不等
2 != 1
// 大于
2 > 1
// 小于
1 < 2
// 大于等于
2 >= 2
// 小于等于
1 <= 3
问号表达式
// 问号表达式
let contentHeight = 40
let hasHeader = true
let rowHeight = contentHeight + ( hasHeader ? 50 : 10)
print(rowHeight)
区间
// 闭区间
for index in 1...5{
print("\(index) times 5 is \(index * 5)")
}
// 半开区间
let names = ["Jordan", "Kobe", "Wade", "James"]
let count = names.count
for i in 0..<count {
print("Person \(i + 1) is called \(names[i])")
}
逻辑运算符
// 逻辑运算符
// 非
let allowedEntry = false
if !allowedEntry {
print("Access Denied")
}
// 与
let enteredDoorCode = true
let passedRetinaScan = false
if enteredDoorCode && passedRetinaScan {
print("Welcome!")
} else {
print("Access Denied!")
}
// 或
let hasDoorKey = false
let knowsOverridePassword = true
if hasDoorKey || knowsOverridePassword {
print("Welcome!")
} else {
print("Access Denied!")
}
