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package gotil |
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import ( |
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"math/rand" |
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"time" |
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) |
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// Shuffle returns a new array of shuffled values, using a version of the Fisher-Yates shuffle. |
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// The default seed is time.Now().UnixNano() |
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// To change seed use gotil.ShuffleSeed() |
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// seed := int64(58239238) |
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// Seed you will get the same sequence of pseudorandom numbers |
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// each time you run the program. |
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// data := []int64{-100, -5, 30, 100} |
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// newData := Shuffle(data) |
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// // Output: [-5 100 -100 30] |
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func Shuffle[T any](s []T) []T { |
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return ShuffleSeed(s, time.Now().UnixNano()) |
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} |
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// ShuffleSeed returns a new array of shuffled values, using a version of the Fisher-Yates shuffle with given seed |
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// To use randomize seed -> gotil.ShuffleSeed() |
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// |
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// seed := time.Now().UnixNano() |
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// Seed you will get the same sequence of pseudorandom numbers |
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// each time you run the program. |
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// |
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// data := []int64{-100, -5, 30, 100} |
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// newData := ShuffleSeed(data, seed) |
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// // Output: [-5 100 -100 30] |
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func ShuffleSeed[T any](s []T, seed int64) []T { |
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rand.Seed(seed) |
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newSlice := copySlice(s) |
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for i := len(newSlice) - 1; i > 0; i-- { // Fisher–Yates shuffle |
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j := rand.Intn(i + 1) |
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newSlice[i], newSlice[j] = newSlice[j], newSlice[i] |
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} |
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return newSlice |
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} |
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gotilty /
gotil
