【EPI】通过位运算求集合的全排列

void generate_power_set(vector& s){
    for(int i = 0; i < (1 << s.size()); i++){
        int x = i;
        while(x) {
            int tar = (log10(x & ~(x-1))) / log10(2);
            cout < vec;
    vec.push_back("A");
    vec.push_back("B");
    vec.push_back("C");
    generate_power_set(vec);
    return 0;
}