46. Permutations

简单回朔题。

class Solution {public:    void permute(vector<int>& nums,vector<int> visit,vector<int>& temp,vector<vector<int>>& result)    {        if(temp.size()==nums.size())            result.push_back(temp);        else        {            for(int i=0;i<nums.size();i++)            {                if(visit[i]==0)                {                    temp.push_back(nums[i]);                    visit[i]=1;                    permute(nums,visit,temp,result);                    visit[i]=0;                    temp.pop_back();                }            }        }    }    vector<vector<int>> permute(vector<int>& nums) {        vector<int> visit(nums.size(),0);        vector<int> temp;        vector<vector<int>> result;        permute(nums,visit,temp,result);        return result;    }};