类似题
Leetcode047全排列(可能含重复元素)-----------回溯法加剪枝
https://blog.csdn.net/qq_52934831/article/details/119578852
地址
https://leetcode-cn.com/problems/combinations/submissions/
描述
思想
人为规定选取顺序:本题为只能从前往后选
代码
class Solution {
public:
vector<int> temp;
vector<vector<int>> ans;
vector<vector<int>> combine(int n, int k) {
dfs(k,n,1);
return ans;
}
void dfs(int k,int n,int index){
if(temp.size()==k) {
ans.push_back(temp);
return ;
}
for(int i=index;i<=n;i++){
temp.push_back(i);
//人为规定选取顺序:本题为只能从前往后选
dfs(k,n,i+1);
temp.pop_back();
}
}
};