C++ 代码

#include<iostream>
#include<cmath>
#include<algorithm>
#include<string>
#include<cstring>
#include<vector>
#include<cstdio>
#include <iomanip>
using namespace std;
int main()
{
    int n;
    cin >> n;
    for (int i = 0; i != 1 << n; ++i)
    {
        for (int j = 0; j != n; ++j)
            if (i & (1 << j))
                cout << j + 1 << ' ';
        cout << endl;
    }
    return 0;
}

算法2

(暴力枚举) $O(n^2)$

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时间复杂度

参考文献

C++ 代码

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