目录
一、题目描述
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二、算法原理
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三、代码实现
cpp
class Solution {
public:
vector<vector<int>> ret;
vector<int> path;
vector<bool> check;
vector<vector<int>> permuteUnique(vector<int>& nums)
{
sort(nums.begin(),nums.end());
int n=nums.size();
check.resize(n,0);
dfs(nums);
return ret;
}
void dfs(vector<int>& nums)
{
if(path.size()==nums.size())
{
ret.push_back(path);
return;
}
int n=nums.size();
for(int i=0;i<n;i++)
{
if(check[i]==false&&(i==0||nums[i]!=nums[i-1]||check[i-1]==true))
{
path.push_back(nums[i]);
check[i]=true;
dfs(nums);
//回复现场
path.pop_back();
check[i]=false;
}
}
}