48 lines
1013 B
Go
48 lines
1013 B
Go
// Package dice contains common functions to generate random number.
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// It also initialize math/rand with the time in seconds at launch time.
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package dice // import "github.com/xtls/xray-core/common/dice"
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import (
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"math/rand"
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)
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// Roll returns a non-negative number between 0 (inclusive) and n (exclusive).
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func Roll(n int) int {
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if n == 1 {
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return 0
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}
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return rand.Intn(n)
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}
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// Roll returns a non-negative number between 0 (inclusive) and n (exclusive).
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func RollDeterministic(n int, seed int64) int {
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if n == 1 {
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return 0
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}
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return rand.New(rand.NewSource(seed)).Intn(n)
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}
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// RollUint16 returns a random uint16 value.
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func RollUint16() uint16 {
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return uint16(rand.Int63() >> 47)
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}
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func RollUint64() uint64 {
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return rand.Uint64()
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}
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func NewDeterministicDice(seed int64) *DeterministicDice {
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return &DeterministicDice{rand.New(rand.NewSource(seed))}
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}
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type DeterministicDice struct {
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*rand.Rand
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}
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func (dd *DeterministicDice) Roll(n int) int {
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if n == 1 {
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return 0
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}
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return dd.Intn(n)
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}
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