Question

C++ Question

I have a text file that contains data from a CD (ex 1. Adagio “MoonLight” Sonata - Ludwig Van Beethoven /n 2. An Alexis - F.H. Hummel and J.N. Hummel)

How do I sort the data by author since that information is in the middle of the string?

Here's what I have that sorts the string from the beginning:

if (file.is_open())
   {
       while (getline(file, line))
       {
           lines.push_back(line);
       }
   }
   else {
       cout << "Could not open file" << endl;
   }

   for (int i = 0; i < lines.size(); i++)
   {

//code

sort(lines.begin(), lines.end()); //sorts from beginning (song)

   for (int i = 0; i < lines.size(); i++)
       cout << lines[i] << "\n";

Need help sorting the author while keeping the entire string.

Answer 1

#include<algorithm>
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <stdio.h>
using namespace std;
int main () {
ifstream myfile;
vector<string> v;
myfile.open ("file.txt");
if (myfile.is_open())
{
   string line;
    while ( getline (myfile,line) )
    {
      v.push_back(line);
    }
    myfile.close();
}
else cout << "Unable to open file";
vector<string>q;
vector<string>j;
    for (int i = 0; i < v.size(); i++){
       string s=v[i];
        string author1=s.substr(0, s.find("-"));
       string author2=s.substr(author1.length()+1,s.length())   ;
       q.push_back(author2+"- "+author1);
    }
    sort(q.begin(),q.end());
      for (int i = 0; i < q.size(); i++){
       string s=q[i];
        string author1=s.substr(0, s.find("-"));
       string author2=s.substr(author1.length()+1,s.length())   ;
       j.push_back(author2+"-"+author1);
    }
    for(int i=0;i<j.size();i++){
       cout <<j[i]<< "\n";
   }
return 0;
}