main.cpp

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include <math.h>

// using namespace std;

namespace patch
{
    template < typename T > std::string to_string( const T& n )
    {
        std::ostringstream stm ;
        stm << n ;
        return stm.str() ;
    }
}

int str_to_int(const std::string& line) {
    std::istringstream is(line);
    int v;
    is >> v;
    return v;
}

void l(std::string log) {
  std::cout << log << std::endl;
}
void l(int log) {
  std::cout << log << std::endl;
}
void l(std::vector <int> log) {
  int log_size = log.size();
  for (int i = 0; i < log_size; i++) {
    std::cout << log[i] << ' ';
  }
  std::cout << std::endl;
}


template <typename T>
std::vector<T> slicing(std::vector<T> const& v,
                  int X, int Y)
{
  return std::vector<T>(v.begin() + X, v.begin() + X + Y);
}
template <typename T>
std::vector<T> slicing(std::vector<T> const& v,
                  int X)
{
  return std::vector<T>(v.begin() + X, v.end());
}


std::vector <int> resort(std::vector <int> digits, int i, std::vector <int> digits_original) {
  std::vector <int> digits_first_part;
  std::vector <int> digits_resort;
  std::vector <int> result;
  digits_first_part = slicing(digits, i);
  digits_resort = slicing(digits, 0, i);
  std::sort(digits_resort.begin(), digits_resort.end());
  std::reverse(digits_first_part.begin(), digits_first_part.end());
  digits_first_part.insert( digits_first_part.end(), digits_resort.begin(), digits_resort.end() );
  return digits_first_part;
}

std::string get(std::string number) {
  int number_size = number.size();
  std::vector <int> digits;
  std::vector <int> digits_original;
  for (int i = number_size - 1; i >= 0; i--) {
    digits.push_back( str_to_int( number.substr(i, 1) ) );
  }
  digits_original = digits;
  bool removed = false;
  for (int i = 0; i <= number_size; i++) {
    if ( digits[i] == 0 && i < number_size ) {
      if ( removed ) {
        digits[i]++;
        digits = resort(digits, i, digits_original);
        break;
      }
      continue;
    }
    if (!removed) {
      digits[i]--;
      removed = true;
      continue;
    }
    if (i == number_size) {
      digits.push_back(0);
    }
    if (digits[i] == 9) {
      continue;
    }
    digits[i]++;
    digits = resort(digits, i, digits_original);
    break;
  }
  int digits_size = digits.size();
  std::string result;
  for (int i = 0; i < digits_size; i++) {
    result += patch::to_string(digits[i]);
  }
  return result;
}


int main() {
  std::ifstream input_file("naksk.dat");
  std::string line;
  std::string result;
  getline( input_file, line );
  result = get(line);
  std::ofstream outfile;
  outfile.open("naksk.rez");
  outfile << result;
  outfile.close();
  return 0;
}