在 std::vector 中索引名称

我做了一个程序，让你输入你的名字并输出它。我找不到索引我的名字的方法。例如，如果您输入“John、Jason、Jam”，您将得到如下编号的姓名：“1:John, 2:Jason, 3:Jam”

int main()
{
    vector<string> names; 

    names.push_back(read_string("Enter a name: ")); 
    names.push_back(read_string("Enter a name: ")); 
    names.push_back(read_string("Enter a name: ")); 

    for(int  i = 0; i < names.size(); i++)
    {
            write_line( names[i]);
    }

    int total;
    total = total_length(names);

    write("Total length: ");
    write_line(total);

    bool has_John; 
    has_John = contains(names, "John");

    if ( has_John ) write_line("Contain's John");


    write_line(shortest_name(names));


    return 0;
}