How to read information from a file written in a certain way and split it into arrays (working with strings)?

Question

C++ / C#

There is a file. It contains records of the form:
<string1>, <string2>, <number1>, <number2>, <number3>;
Records are separated by ";".
It is necessary to read all the records from the file and sum the numbers. How to do it? Help me please.

Answer 1

well then

spoiler

filein.txt
Petya,K221,1,2,3;Vasya,K222,4,5,6;Senya,K223,7,8,0;Goga,K224,1,2,3;

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <iterator>
#include <algorithm>
using namespace std;

template<typename X = int>
struct Data
{
  X one;
  X two;
  X three;
  Data(X x1 = 0, X x2 = 0, X x3 = 0) : one{x1}, two{x2}, three{x3}
  {}
};

template<typename X = int>
struct DataRecord
{
  pair<string, string> text;
  Data<X> data;
  DataRecord(string _s1 = {}, string _s2 = {},
             X _x1 = 0, X _x2 = 0, X _x3 = 0)
    : text{_s1, _s2}, data{_x1, _x2, _x3}
  {}
};

template<typename X = int>
istream& operator>>(istream& is, DataRecord<X>& record)
{
  char c;
  getline(is, record.text.first, ',');
  getline(is, record.text.second, ',');
  is >> record.data.one;
  is >> c;
  if(c == ',')
  {
    is >> record.data.two;
    is >> c;
    if(c == ',')
    {
      is >> record.data.three;
    }
  }
  is >> c;
  if(c != ';')
  {
    is.clear(ios_base::failbit);
  }
  return is;
}

struct DataSet
{
  vector<DataRecord<>> records;
  DataSet() : records{}{}
  void load(string filename) noexcept;
  Data<> sumsByColumns() noexcept;
};

void DataSet::load(string filename) noexcept
{
  ifstream in(filename);
  if(!in)
  {
    //...
    return;
  }
  copy(istream_iterator<DataRecord<>>{in}, {}, back_inserter(records));
}

Data<> DataSet::sumsByColumns() noexcept
{
  Data<> result;
  for(const auto& rec : records)
  {
    result.one   += rec.data.one;
    result.two   += rec.data.two;
    result.three += rec.data.three;
  }
  return result;
}

int main()
{
  DataSet ds;
  ds.load("C:\\infile.txt");
  Data<> result{ds.sumsByColumns()};

  for(const auto& rec : ds.records)
  {
    cout << rec.text.first << '\t'
         << rec.text.second << '\t'
         << rec.data.one << '\t'
         << rec.data.two << '\t'
         << rec.data.three << '\n';// Если формат записей в файле
                                   // построчный '\n' нужно убрать.
  }

  cout << "\nTotal:\t\t"
       << result.one << '\t'
       << result.two << '\t'
       << result.three << endl;
}

OUT
Petya   K221    1       2       3
Vasya   K222    4       5       6
Senya   K223    7       8       0
Goga    K224    1       2       3

Total:          13      17      12

Answer 2

ifstream f("./dat.txt");

  
  for (std::string line; std::getline(f, line);) {
    stringstream ss(line);
    long S = 0;

    for(std::string item;std::getline(ss, item,','); ) {
      try{
        int v = std::stoi(item);
        if (v > 0) {
          S += v;
        }
      }
      catch (exception&) {
      }
    }
    cout << S << endl;
  }

Answer 3

Look here .