编辑代码

// 练习
var sum = 0
for number in 1...100 {
    sum += number
}
print("Sum of 1+2+...+98+100 = \(sum)") // 输出1到100的和

var number = 0
sum = 0
while number <= 100 {
    sum += number
    number += 1
}
print("Sum of 1+2+...+98+100 = \(sum)") // 输出1到100的和

number = 0
sum = 0
repeat {
    sum += number
    number += 1
} while number <= 100
print("Sum of 1+2+...+98+100 = \(sum)") // 输出1到100的和

var score = 88
if score < 60 {
    print("Fail")
} else if score < 70 {
    print("Pass")
} else if score < 80 {
    print("Common")
} else if score < 90 {
    print("Good")
} else {
    print("Excellent")
}

var grade = ""
switch score {
    case 0...59: grade = "Fail"
    case 60...69: grade = "Pass"
    case 70...79: grade = "Common"
    case 80...89: grade = "Good"
    case 90...100: grade = "Excellent"
    default: print("Unreasonable Score!")
}
print("Grade is \(grade)")

var subject = "Math"
grade = "Excellent"
var subjectInfo = (grade, subject)

switch subjectInfo {
case ("Fail", _): print("Fail")
case ("Pass", _): print("Pass")
case ("Excellent", "Math"): print("Math is Excellent")
case ("Excellent", "Physics"): print("Physics is Excellent")
default: print("Common or Good")
}

subjectInfo = ("Pass", "Math")
switch subjectInfo {
case ("Fail", let subject): print("Subject \(subject) is Fail")
case ("Pass", let subject): print("Subject \(subject) is Pass")
case ("Excellent", "Math"): print("Math is Excellent")
case ("Excellent", "Physics"): print("Physics is Excellent")
default: print("Common or Good")
}

subjectInfo = ("Excellent", "Physics")
switch subjectInfo {
case ("Fail", let subject): print("Subject \(subject) is Fail")
case ("Pass", let subject): print("Subject \(subject) is Pass")
case let (grade, subject) where (subject == "Math" || subject == "Physics") && grade == "Excellent": print("\(subject) is \(grade)")
default: print("Common or Good")
}

var product = 1
var count = 1
while count <= 100 {
    product *= count
    count += 1
    if product > 100 {
        print("count is \(count), product is \(product).")
        break
    }
}
print("Cycle is stopped!")
print("count is \(count), product is \(product).")