54 lines
1.2 KiB
Go
54 lines
1.2 KiB
Go
// Copyright 2023 The etcd Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package random
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import (
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"math/rand"
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"strings"
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)
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func RandString(size int) string {
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data := strings.Builder{}
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data.Grow(size)
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for i := 0; i < size; i++ {
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data.WriteByte(byte(int('a') + rand.Intn(26)))
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}
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return data.String()
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}
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func RandRange(start, end int64) int64 {
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return rand.Int63n(end-start) + start
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}
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type ChoiceWeight[T any] struct {
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Choice T
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Weight int
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}
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func PickRandom[T any](choices []ChoiceWeight[T]) T {
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sum := 0
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for _, op := range choices {
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sum += op.Weight
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}
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roll := rand.Int() % sum
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for _, op := range choices {
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if roll < op.Weight {
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return op.Choice
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}
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roll -= op.Weight
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}
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panic("unexpected")
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}
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