Create CRC-16.go

add hacktoberfest label

Author: dev-priyanshu15

checksum/CRC-16.go

@@ -0,0 +1,26 @@
+// Package checksum provides functions for calculating various checksum values.
+package checksum
+
+import "fmt"
+
+// CRC16 computes the CRC-16 checksum of the input data.
+func CRC16(data []byte) uint16 {
+    var crc uint16 = 0xFFFF
+    for _, b := range data {
+        crc ^= uint16(b)
+        for i := 0; i < 8; i++ {
+            if crc&0x0001 != 0 {
+                crc = (crc >> 1) ^ 0xA001
+            } else {
+                crc >>= 1
+            }
+        }
+    }
+    return crc
+}
+
+// CRC16Hex computes the CRC-16 checksum of a string and returns it as a hexadecimal string.
+func CRC16Hex(input string) string {
+    crc := CRC16([]byte(input))
+    return fmt.Sprintf("%04X", crc)
+}