func LexicographicPermute(n int) [][]int {
var results [][]int
perm := common.GenerateNumbers(n)
results = append(results, perm)
findIJ := func(perm []int) (i, j int) {
i = -1
j = -1
for k := 0; k < len(perm)-1; k++ {
if perm[k] < perm[k+1] {
i = k
}
if i != -1 && perm[k+1] > perm[i] {
j = k + 1
}
}
return
}
i, j := findIJ(perm)
fmt.Println(perm, i, j)
for i != -1 {
perm = append([]int(nil), perm...)
common.SwapElement(perm, i, j)
common.ReverseSliceRange(perm, i+1, n-1)
results = append(results, perm)
i, j = findIJ(perm)
fmt.Println(perm, i, j)
}
return results
}
func main() {
n := 5
elems := common.GenerateNumbers(n)
// fmt.Println(elems)
flags := common.GenerateFlagNumbers(n) // 1,2,4,8....
count := common.Power(2, n)
allSubsets := [][]int{}
for i := 0; i < count; i++ {
subset := []int{}
for k, flag := range flags {
if i&flag != 0 {
subset = append(subset, elems[k])
}
}
allSubsets = append(allSubsets, subset)
}
for _, subset := range allSubsets {
fmt.Println(subset)
}
}