題目地址：https://www.acwing.com/problem/content/87/
AC代碼
class Solution {
public:
vector<vector<int>> res;
vector<int> path;
bool canSwap(vector<int>& v,int start ,int end){
for(int i=start;i<end;++i) if(v[i]==v[end]) return false;
return true;
}
void f(vector<int>& v,int start,int len){
if(start==len){
res.push_back(path);
return;
}
for(int i=start;i<len;++i){
if(canSwap(v,start,i)){
path.push_back(v[i]);
swap(v[i],v[start]);
f(v,start+1,len);
swap(v[i],v[start]);
path.pop_back();
}
}
}
vector<vector<int>> permutation(vector<int>& nums) {
sort(nums.begin(),nums.end());
f(nums,0,nums.size());
return res;
}
};
總結(jié)
題解參考討論區(qū)
