missing return in global function expected to return 'Int'-CodePudding

I want to define a function to return a sqrt of a number. but Swift give me an error

func RenderNumber(_ number:Int) -> Int{
    for x in 1...number{
        if x*x == number{
            return x
        }
    }
}

print(RenderNumber(25))

CodePudding user response：

If a function has a return value you have to return something in any case.

If the square root of number is not an integer the condition x*x == number will never be true.

My suggestion is to return an optional and write the body of the function in a swiftier way

func renderNumber(_ number: Int) -> Int? {
    if number <= 0 { return nil }
    return (1...number).first{$0 * $0 == number}
}

CodePudding user response：

What you have done is fine, but you are not saying what if condition fails. There is no return if x*x!=number

So update function to below.

func RenderNumber(_ number:Int) -> Int{
    var returnValue : Int = 0
    for x in 1...number{
        if x*x == number{
            returnValue = x
            break
        }
    }
    return returnValue
}

So here it will return 0 if x*x!=number