gf/encoding/ghash/ghash_bkdr.go
2022-01-13 21:31:23 +08:00

32 lines
805 B
Go

// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package ghash
// BKDR implements the classic BKDR hash algorithm for 32 bits.
func BKDR(str []byte) uint32 {
var (
seed uint32 = 131 // 31 131 1313 13131 131313 etc..
hash uint32 = 0
)
for i := 0; i < len(str); i++ {
hash = hash*seed + uint32(str[i])
}
return hash
}
// BKDR64 implements the classic BKDR hash algorithm for 64 bits.
func BKDR64(str []byte) uint64 {
var (
seed uint64 = 131 // 31 131 1313 13131 131313 etc..
hash uint64 = 0
)
for i := 0; i < len(str); i++ {
hash = hash*seed + uint64(str[i])
}
return hash
}