Refactor Evaluate to simplify error checks and bit counting

Removed redundant length checks and streamlined error handling for XOR operations. Simplified the loop to count differing bits by iterating directly over the XOR result. This improves code readability and reduces duplication.

evaluate.go

@@ -5,20 +5,12 @@ import (
 )
 
 func Evaluate(a, b []byte) (bitDiffCount int, err error) {
-	// Check if the lengths of the strings are the same
-	if len(a) != len(b) {
-		return 0, fmt.Errorf("byte strings are of different lengths %d and %d", len(a), len(b))
-	}
-	if len(a) != 32 || len(b) != 32 {
-		return 0, fmt.Errorf("input nilsimsa hashes must be 32 bytes each, got %d and %d",
-			len(a), len(b))
-	}
-
-	// Count the differing bits
 	var c []byte
-	c, err = XOR(a, b)
-	for i := 0; i < len(a); i++ {
-		bitDiffCount += countBits(c[i])
+	if c, err = XOR(a, b); err != nil {
+		return
+	}
+	for _, v := range c {
+		bitDiffCount += countBits(v)
 	}
 	return bitDiffCount, nil
 }