编辑代码

var myString = "Hello world!     -  swift.jsrun.net"
print(myString)


var list:[Int] = [1,2,3,4];
var listb:[String:Int] = ["11111":1,"22222":2];
list.append(5);
print(list);
print(listb);

for field in 0..<list.count{
    if field > 3 {
        list[field] += 3
    }   
}

print(list);
for key in listb {
    print(key);
}


var test:String? = "test";
test = nil
print(test)


var optionalName: String? = "John Appleseed"
var greeting = "Hello!"
if let name = optionalName {
    greeting = "Hello, \(name)"
}


var nickName: String? = nil
var fullName: String = "John Appleseed"
var informalGreeting = "Hi \(nickName ?? fullName)"
if var informalGreeting = nickName {
    fullName = "Hi \(fullName)"
}
print(informalGreeting);
print(fullName);



var alist:[String:[Int]] = [
    "Prime": [2, 3, 5, 7, 11, 13],
    "Fibonacci": [1, 1, 2, 3, 5, 8],
    "Square": [1, 4, 9, 16, 25],
];
var maxField:String = "";
var maxValue:Int = 0;
var alistTotal: [String:Int] = [:];
for (key,children) in alist {
    print(key);
    var total = 0;
    for val in children {
        total += val;
    }
    alistTotal[key] = total
    if total > maxValue {
        maxValue = total;
        maxField = key
    }
}

print(alistTotal);
print(maxValue);
print(maxField);



for i in -2 ..< 0 {
    print(i)
}


func greet(a person: String, _ day: String) -> String {
    return "Hello \(person), today is \(day)."
}
print(greet(a: "Wednesday","bbbb"))


func testFunc() -> ((Int) -> Int) {
    func a(ab:Int) -> Int {
        return ab + 10
    }
    return a
}

var funca = testFunc()
print(funca(7))



func hasAnyMatches(list: [Int], condition: (Int) -> Bool) -> Bool {
    for item in list {
        if condition(item) {
            return true
        }
    }
    return false
}
func lessThanTen(number: Int) -> Bool {
    return number < 10
}
var numbers = [12, 12, 17, 1]
print(hasAnyMatches(list: numbers, condition: lessThanTen))