题解 | #没有重复项数字的全排列#

package main

/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 *
 * @param nums int整型一维数组
 * @return int整型二维数组
 */
func permute( nums []int ) [][]int {
    // write code here
    var res [][]int
    var path []int
    used := make([]bool, len(nums))
    backtrack(nums,path,&res,used)
    return res
}

func backtrack(nums []int, path []int,res *[][]int,used []bool){    
    if len(nums) == len(path) {
        temp := make([]int, len(path))
        copy(temp, path)
        *res = append(*res, temp)
        return
    }
    for i, num := range nums {
        if  used[i] {
            continue
        }
        path = append(path, num)
        used[i] = true
        backtrack(nums, path, res, used)
        path = path[:len(path) -1 ]
        used[i] = false
    }
}