golang力扣leetcode 47.全排列II

package main
import "sort"
func permuteUnique(nums []int) [][]int {
  result := make([][]int, 0)
  list := make([]int, 0)
  vis := make([]bool, len(nums))
  sort.Ints(nums)
  backtrack(nums, vis, list, &result)
  return result
}
func backtrack(nums []int, vis []bool, list []int, result *[][]int) {
  if len(list) == len(nums) {
    ans := make([]int, len(list))
    copy(ans, list)
    *result = append(*result, ans)
  }
  for i := 0; i < len(nums); i++ {
    if vis[i] == false {
      if i != 0 && nums[i] == nums[i-1] && vis[i-1] == false {
        continue
      }
      vis[i] = true
      list = append(list, nums[i])
      backtrack(nums, vis, list, result)
      list = list[0 : len(list)-1]
      vis[i] = false
    }
  }
}