c++ - 在另一个 vector 中搜索一个 vector

Question

我想彻底搜索一个 vector ，看看是否出现了一个元素。一旦这个元素与其他元素一起出现，我想重新搜索原始元素以查看第二个元素是否出现在 vector 中的其他位置。最终结果应显示找到的第一个元素，然后显示第二个元素出现位置的信息。

void searchband()
{

    ifstream artist("newartist.txt");
    string SBand;
    cout << "Please enter the band you want to seach" << endl;
    cin >> SBand;
    system("CLS");
    while (artist >> forname >> surname >> bandnum)
    {

        band.clear();
        for (int i = 0; i < bandnum; i++)
        {
            string tmp;
            artist >> tmp;
            band.push_back(tmp);
        }
        artist >> role;
        if (find(band.begin(), band.end(), SBand) != band.end())
        {


            cout << forname << " " << surname << endl;
            cout << "Played for: ";
            ostream_iterator<string> output_iterator(cout, " ");
            copy(band.begin(), band.end(), output_iterator);
            cout << " " << endl;
            cout << " " << endl;
            newband = band;

        }
            if (find(band.begin(), band.end(), newband) != band.end())
            {


                cout << forname << " " << surname << endl;
                cout << "Played for: ";
                ostream_iterator<string> output_iterator(cout, " ");
                copy(band.begin(), band.end(), output_iterator);
                cout << " " << endl;
                cout << " " << endl;

            }
            system("pause");
            cin.get();
            main();

    }
}

获取错误码

error C2678: binary '==' : no operator found which takes a left-hand operand of type std::basic_string<char,std::char_traits<char>,std::allocator<char>> (or there is no acceptable conversion)

我想可能是因为

vector<string> = newband

但这是我能想到的将 vector 信息传递给另一个 vector 的唯一方法

Answer 1

std::find_first_of做你正在寻找的:

Searches the range [first, last) for any of the elements in the range [s_first, s_last).

示例(也取自 cppreference ):

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

int main()
{
    std::vector<int> v{0, 2, 3, 25, 5};
    std::vector<int> t{3, 19, 10, 2};

    auto result = std::find_first_of(v.begin(), v.end(), t.begin(), t.end());

    if (result == v.end()) {
        std::cout << "no elements of v were equal to 3, 19, 10 or 2\n";
    } else {
        std::cout << "found a match at "
                  << std::distance(v.begin(), result) << "\n";
    }
 }