46. 全排列

46. 全排列

var mark []int
var n int
func permute(nums []int) [][]int {
    n =len(nums)
    res:= make([][]int,0)
    if n<=0{
        return res
    }
    mark = make([]int,n)
    path :=make([]int,0)
    dfs(nums,path,&res)
    return res
}
func dfs(nums[]int,path[]int,res*[][]int)  {
    if len(path)==n {
        tmp := make([]int,n)
        copy(tmp,path)
        *res =append(*res,tmp)
        return
    }
    for i :=0;i<n;i++{
        if mark[i]==1 {//减掉枝叶
            continue
        }
        path = append(path,nums[i])
        mark[i]=1
        dfs(nums,path,res)
        path = path[:len(path)-1]
        mark[i]=0
    }
}