Find delimiter and get other content C++

#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <cstddef> // std::size_t

/* finddelim.cpp */

using std::cout; using std::cin; using std::cerr;
using std::endl; using std::string; using std::vector;
using std::ifstream;
string readFileIntoString(const string path) {
    ifstream input_file(path);
    if (!input_file.is_open()) {
        cerr << "Could not open the file - '"
             << path << "'" << endl;
        exit(EXIT_FAILURE);
    }
    string f= string((std::istreambuf_iterator<char>(input_file)), std::istreambuf_iterator<char>());
    input_file.close();
    return f;
}
vector<string> findDigits(string data)
{
    std::size_t pos;
    string delim="-";
    vector <string>numbers;
  while ((pos = data.find(delim)) != string::npos) {
        numbers.push_back(data.substr(0, pos));
        data.erase(0, pos + delim.length());
    }// get last numbera on tail if any
    if(data.size()>0)
    numbers.push_back(data);
return numbers;
}
vector<string> removeEmpties(vector<string> v)
{
    auto isEmptyOrBlank = [](const std::string &s) {
    return s.find_first_not_of(" \t") == std::string::npos;
    };
    v.erase(std::remove_if(v.begin(), v.end(),
    isEmptyOrBlank), v.end());
return v;
}
int main (){
/* test file
--242----2-343---3-33---943-3--3-5-223--848344-  */
string filename="finddigits";
string file_contents;
    file_contents = readFileIntoString(filename);
   cout << file_contents << endl;
   vector<string>num=
    removeEmpties(findDigits(readFileIntoString(filename)));
for(const auto &n:num)
    cout<< n <<" ";
    cout<<endl;
exit(EXIT_SUCCESS);
}