20 lines
390 B
Go
20 lines
390 B
Go
package gen
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// cross returns the cross product of the lists in x.
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func cross(x [][]string) [][]string {
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r := [][]string{nil}
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for _, s := range x {
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var nxt [][]string
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for _, pre := range r {
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for _, a := range s {
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concat := make([]string, len(pre), len(pre)+1)
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copy(concat, pre)
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concat = append(concat, a)
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nxt = append(nxt, concat)
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}
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}
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r = nxt
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}
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return r
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}
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