Write a program that asks the user for two file names. The first file will be opened for input and the second file will be opened for output. (It will be assumed that the first file contains sentences that end with a period.) The program will read the contents of the first file and change all the letters to lowercase except the first letter of each sentence, which should be made uppercase. The revised contents should be stored in the second file.

#include <iostream>

#include <fstream>

#include <string>

using namespace std;

int main()

{

//First we declare string variables to store file names for input and output

   string inputName;

   string outputName;

   string sentence;

// Then declare char variable to get current char

   char ch;

//The following section will prompt theuser to enter the file names and read

   cout << "Enter input file name:\n";

   cin >> inputName;

   cout << "Enter output file name:\n";

   cin >> outputName;

//ignore newline character left inside keyboard buffer

   cin.ignore();

//Next we define the input and output files to be opened

   ifstream inputFile(inputName);

   ofstream outputFile(outputName);

   if(!inputFile && !outputFile){

       cout << "Error while opening the files!\n";

       cout << "Please try again!\n";

       //end program immediately

       return 0;

   }

//Using this loop to get lines one by one, delimited by '.'

   while(getline(inputFile, sentence, '.')){

       //bool variable to store if we have already

       //printed capital first letter

       bool alreadyCapitalized = false;

       //Using of for loop on all characters of sentence

       for(int counter = 0; counter < sentence.length(); counter++){

           //if not alphabetical character,

           //so whitespace or newline, print as is

           if(!isalpha(sentence[counter]))

               outputFile << sentence[counter];

       //Condition statement for if it is alphabetical and no capitalization has been done, print it as uppercase

           if(!alreadyCapitalized && isalpha(sentence[counter])){

               outputFile << (char)toupper(sentence[counter]);

               alreadyCapitalized = true;

           }

           //otherwise print this condition as lowercase

           else if(alreadyCapitalized)

               outputFile << (char)tolower(sentence[counter]);

       }

       //Printing of the output sentence with period in the end

       outputFile << ".";

   }

   //Closing the files

   inputFile.close();

   outputFile.close();

   return 0;

}