В файле заменить все слова максимальной длины на слова минимальной длины

#include <iostream>
#include <fstream>
#include <iterator>
#include <vector>
#include <string>
#include <cctype>
#include <algorithm>
 
//=============================================================================
int main()
{
  std::ifstream inStream("Test.txt");
  if (!inStream)
  {
    std::cout << "Can't open file" << std::endl;
    return 1;
  }
 
  std::istream_iterator<std::string> in(inStream), inEnd;
  std::vector<std::string> file(in, inEnd);
  std::vector<size_t> lengths;
 
  for (size_t j = 0, sz = file.size(); j != sz; ++j)
  {
    std::string tempStr = file[j];
 
    if (std::ispunct(tempStr[tempStr.size() - 1]))
      tempStr.pop_back();
 
    lengths.push_back(tempStr.size());
  }
 
  auto itMax = std::max_element(lengths.cbegin(), lengths.cend());
  size_t max = *itMax,
         min = lengths[itMax - lengths.cbegin()],
         minIndx = 0;
 
  for (size_t j = 0, sz = lengths.size(); j != sz; ++j)
    if (min > lengths[j] &&
        lengths[j] != 0)
    {
      min = lengths[j];
      minIndx = j;
    }
 
  std::string minStr = file[minIndx];
  if (std::ispunct(minStr[minStr.size() - 1]))
    minStr.pop_back();
 
  for (size_t j = 0, sz = lengths.size(); j != sz; ++j)
  {
    if (lengths[j] == max)
    {
      if (std::ispunct(file[j][file[j].size() - 1]))
        file[j] = minStr + file[j][file[j].size() - 1];
      else
        file[j] = minStr;
    }
  }
 
  inStream.close();
  std::ofstream outStream("Test.txt");
  if (!outStream)
  {
    std::cout << "Can't open file" << std::endl;
    return 2;
  }
 
  std::ostream_iterator<std::string> out(outStream, " ");
  for (const auto& j : file)
    *out++ = j;
 
  return 0;
}

std::ostream_iterator<std::string> out(outStream, "\n");

#include <iostream>
#include <fstream>
#include <sstream>
#include <iterator>
#include <vector>
#include <string>
#include <cctype>
 
//=============================================================================
int main()
{
  std::ifstream inStream("Test.txt");
  if (!inStream)
  {
    std::cout << "Can't open file" << std::endl;
    return 1;
  }
 
  std::string temp;
  std::vector<std::string> file;
  while (getline(inStream, temp))
    file.push_back(temp);
 
  std::string minStr, maxStr;
  for (size_t j = 0, sz = file.size(); j != sz; ++j)
  {
    std::istringstream iss(file[j]);
 
    while (iss >> temp)
    {
      if (minStr.empty())
        minStr = temp;
      if (maxStr.empty())
        maxStr = temp;
 
      if (std::ispunct(temp[temp.size() - 1]))
        temp.pop_back();
 
      if (minStr.size() > temp.size())
        minStr = temp;
      if (maxStr.size() < temp.size())
        maxStr = temp;
    }
  }
 
  for (size_t j = 0, sz = file.size(); j != sz; ++j)
  {
    size_t indx = 0;
    while ((indx = file[j].find(maxStr, indx)) != std::string::npos)
    {
      file[j].replace(indx, maxStr.size(), minStr);
      indx = 0;
    }
  }
 
  inStream.close();
  std::ofstream outStream("Test.txt");
  if (!outStream)
  {
    std::cout << "Can't open file" << std::endl;
    return 2;
  }
 
  std::ostream_iterator<std::string> out(outStream, "\n");
  for (const auto& j : file)
    *out++ = j;
 
  return 0;
}