32 lines
653 B
Go
32 lines
653 B
Go
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package services
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import (
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"math/rand"
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"strings"
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)
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const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
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const (
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letterIdxBits = 6
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letterIdxMask = 1<<letterIdxBits - 1
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letterIdxMax = 63 / letterIdxBits
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)
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func RandString(length int) string {
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builder := strings.Builder{}
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builder.Grow(length)
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for idx, cache, remain := length-1, rand.Int63(), letterIdxMax; idx >= 0; {
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if remain == 0 {
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cache, remain = rand.Int63(), letterIdxMax
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}
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if idx := int(cache & letterIdxMask); idx < len(letterBytes) {
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builder.WriteByte(letterBytes[idx])
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idx--
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}
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cache >>= letterIdxBits
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remain--
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}
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return builder.String()
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}
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