huangzj
47 lines
798 B
Go
47 lines
798 B
Go
//通过hash算法获取字符串对应的哈希值
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package util
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import (
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"bytes"
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"hash/crc32"
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"math/big"
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)
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func bigInt(s string) (*big.Int, bool) {
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bInt := new(big.Int)
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return bInt.SetString(s, 10)
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}
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func UseBigIntMod(s string, mod int) int64 {
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b, br := bigInt(s)
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if !br {
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panic("该方法只可用于大数mod计算")
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}
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result := b.Mod(b, new(big.Int).SetInt64(int64(mod)))
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return result.Int64()
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}
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func calBytesSum(s string) int {
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var sum int
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for _, b1 := range bytes.NewBufferString(s).Bytes() {
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sum = sum + int(b1)
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}
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return sum
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}
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func Mod(s string, mod int) int {
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sum := calBytesSum(s)
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return sum % mod
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}
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func crc32Change(s string) uint32 {
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return crc32.ChecksumIEEE([]byte(s))
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}
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func Crc32Mode(s string, mod int) int {
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u := crc32Change(s)
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return int(u) % mod
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}
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