带有附加谓词参数的std::set_union替代方案，用于合并交叉点中的元素

#include <iostream>
#include <algorithm>
#include <vector>

bool customCompare(int a, int b) {
    // 自定义的比较函数，根据需要进行修改
    return a < b;
}

int main() {
    std::vector<int> set1 = {1, 2, 3, 4, 5};
    std::vector<int> set2 = {3, 4, 5, 6, 7};
    std::vector<int> result;

    std::merge(set1.begin(), set1.end(), set2.begin(), set2.end(), std::back_inserter(result), customCompare);

    for (int num : result) {
        std::cout << num << " ";
    }
    std::cout << std::endl;

    return 0;
}

#include <iostream>
#include <vector>
#include <algorithm>

bool customCompare(int a, int b) {
    // 自定义的比较函数，根据需要进行修改
    return a < b;
}

int main() {
    std::vector<int> set1 = {1, 2, 3, 4, 5};
    std::vector<int> set2 = {3, 4, 5, 6, 7};
    std::vector<int> result;

    result.reserve(set1.size() + set2.size());
    result.insert(result.end(), set1.begin(), set1.end());
    result.insert(result.end(), set2.begin(), set2.end());

    std::sort(result.begin(), result.end(), customCompare);

    for (int num : result) {
        std::cout << num << " ";
    }
    std::cout << std::endl;

    return 0;
}