Answer:
#include <iostream>
#include<string>
#include<fstream>
using namespace std;
void evaluateBook(string bookName);
int countCharacters(string bookLine);
int countLetters(string bookLine);
int totalPunctuations(string bookLine);
int main()
{
 evaluateBook("demo-book.txt");
 return 0;
}
int countCharacters(string bookLine) {
 return bookLine.length();
}
int countLetters(string bookLine) {
 int counter = 0;
 for (int i = 0; i < bookLine.length(); i++) {
   if ((bookLine[i] >= 'a' && bookLine[i] <= 'z') || (bookLine[i] >= 'A' && bookLine[i] <= 'Z')) {
     counter++;
   }
 }
 return counter;
}
int totalPunctuations(string bookLine) {
 int counter = 0;
 for (int i = 0; i < bookLine.length(); i++) {
   if (bookLine[i]=='\.' || bookLine[i]=='\,' || bookLine[i]=='\"' || bookLine[i]=='\'') {
     counter++;
   }
 }
 return counter;
}
void evaluateBook(string bookName) {
 ifstream in(bookName);
 int totalVisibleCharacters = 0,totalLetters=0,numberOfPunctuations=0;
 if (!in) {
   cout << "File not found!!\n";
   exit(0);
 }
 string bookLine;
 while (getline(in, bookLine)) {
   totalVisibleCharacters += countCharacters(bookLine);
   totalLetters += countLetters(bookLine);
   numberOfPunctuations += totalPunctuations(bookLine);
 }
 cout << "Total Visible charcters count: "<<totalVisibleCharacters << endl;
 cout << "Total letters count: " << totalLetters << endl;
 cout << "Total punctuations count: " << numberOfPunctuations<< endl;
}
Explanation:
