Swift 4 Extension for finding the biggest integer value from an array of integers

FindMaxInteger.swift

extension Array where Element: SignedInteger {
    
    static func findMaxInt(arr:[Int]) -> Int{
        
        var previous = Int()
        var max = Int()
        
        arr.forEach { (n) in
            max = n > previous && n > max ? n : max
            previous = n;
        }
        
        return max
    }
}