用c++实现集合的运算操作，包括交集、并集、差集、幂集、任意m元子集

以下是用C++实现集合的运算操作的示例代码：

#include <iostream>
#include <set>
#include <cmath>

using namespace std;

// 打印集合
void printSet(const set<int>& s) {
    cout << "{ ";
    for (auto x : s) {
        cout << x << " ";
    }
    cout << "}" << endl;
}

// 交集
set<int> intersection(const set<int>& s1, const set<int>& s2) {
    set<int> result;
    for (auto x : s1) {
        if (s2.count(x)) {
            result.insert(x);
        }
    }
    return result;
}

// 并集
set<int> unionSet(const set<int>& s1, const set<int>& s2) {
    set<int> result = s1;
    result.insert(s2.begin(), s2.end());
    return result;
}

// 差集
set<int> difference(const set<int>& s1, const set<int>& s2) {
    set<int> result;
    for (auto x : s1) {
        if (!s2.count(x)) {
            result.insert(x);
        }
    }
    return result;
}

// 幂集
set<set<int>> powerSet(const set<int>& s) {
    set<set<int>> result;
    int n = s.size();
    int pow_n = pow(2, n);
    for (int i = 0; i < pow_n; i++) {
        set<int> subset;
        for (int j = 0; j < n; j++) {
            if ((i >> j) & 1) {
                subset.insert(*next(s.begin(), j));
            }
        }
        result.insert(subset);
    }
    return result;
}

// m元子集
set<set<int>> mSubset(const set<int>& s, int m) {
    set<set<int>> result;
    if (m == 0) {
        result.insert({});
        return result;
    }
    if (m == s.size()) {
        result.insert(s);
        return result;
    }
    int x = *s.begin();
    set<int> rest = difference(s, { x });
    set<set<int>> subsetsWithoutX = mSubset(rest, m);
    set<set<int>> subsetsWithX = mSubset(rest, m - 1);
    for (auto subset : subsetsWithX) {
        subset.insert(x);
        result.insert(subset);
    }
    result.insert(subsetsWithoutX.begin(), subsetsWithoutX.end());
    return result;
}

int main() {
    set<int> s1 = { 1, 2, 3, 4 };
    set<int> s2 = { 3, 4, 5, 6 };
    cout << "s1 = ";
    printSet(s1);
    cout << "s2 = ";
    printSet(s2);
    cout << endl;

    set<int> s3 = intersection(s1, s2);
    cout << "s1 ∩ s2 = ";
    printSet(s3);

    set<int> s4 = unionSet(s1, s2);
    cout << "s1 ∪ s2 = ";
    printSet(s4);

    set<int> s5 = difference(s1, s2);
    cout << "s1 - s2 = ";
    printSet(s5);

    set<set<int>> s6 = powerSet(s1);
    cout << "P(s1) = " << endl;
    for (auto subset : s6) {
        printSet(subset);
    }

    set<set<int>> s7 = mSubset(s1, 2);
    cout << "2元子集 = " << endl;
    for (auto subset : s7) {
        printSet(subset);
    }

    return 0;
}

示例输出：

s1 = { 1 2 3 4 }
s2 = { 3 4 5 6 }

s1 ∩ s2 = { 3 4 }
s1 ∪ s2 = { 1 2 3 4 5 6 }
s1 - s2 = { 1 2 }

P(s1) = 
{ }
{ 1 }
{ 1 2 }
{ 1 2 3 }
{ 1 2 3 4 }
{ 1 2 4 }
{ 1 3 }
{ 1 3 4 }
{ 1 4 }
{ 2 }
{ 2 3 }
{ 2 3 4 }
{ 2 4 }
{ 3 }
{ 3 4 }
{ 4 }

2元子集 = 
{ 1 2 }
{ 1 3 }
{ 1 4 }
{ 2 3 }
{ 2 4 }
{ 3 4 }