             }
             s1 = (s1 + UInt32(c))
             s2 = (s2 + s1)
-            self.counter++
+            self.counter += 1
         }
     }
-    
+
     /// Get CRC of current state
     ///
     /// - returns: 32 Bits of CRC (current state)
     public var crc: UInt32 {
         return (self.s2 << 16) | self.s1
     }
-    
+
     /// Calculate Adler32 CRC of String
     ///
     /// - parameter string: the string to calculate the CRC for

        let data = [UInt8](string.utf8)
        return self.crc(data: data)
    }
    
    /// Calculate Adler32 CRC of Data
    ///
    /// - parameter data: data to calcuclate the CRC for


/// Adler32 checksumming
public class Adler32 {

    private var s1: UInt32 = 1
    private var s2: UInt32 = 0
    private var counter: Int = 0

    /// Add data to checksum
    ///
    /// - parameter data: data to add to the checksum
    public func addData(data: [UInt8]) {
        for c in data {
