Question

C++: Make sure to identify codes with comments and no other programming other than C++ (please make it simple as possible)

DON'T COPY CODES FROM OTHER ANSWERS

Create a program that:

          - in main

                   - opens the file provided for input

                   - calls a function to determine how many lines are in the file

                   - creates an array of the proper size

                   - calls a function to read the file and populate the array

                   - calls a function to write out the contents of the array in reverse order

                      output file should be named 'reverse_output.txt'

Answer 1

Screenshot

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Program

//Header files
#include <iostream>
#include<string>
#include<fstream>
using namespace std;
//Function prototypes
void findLineCount(ifstream& in, int &count);
void readfile(ifstream& in, int count,int* arr);
int main()
{
   //Input file name object
   ifstream in("C:/Users/deept/Desktop/input.txt");
   //Ariable for lines of file
   int lineCount=0;
    //Array for store data
   int *intArray=NULL;
   //Error check in opening file
   if (!in) {
       cout << "File not open!!!" << endl;
       exit(0);
   }
   //Function call to get lines in the file
   findLineCount(in,lineCount);
   //Close the file
   in.close();
   //Create file open
   in.open("C:/Users/deept/Desktop/input.txt");
   //Error check
   if (!in) {
       cout << "File not open!!!" << endl;
       exit(0);
   }
   //allocate array size
   intArray=new int[lineCount];
   //Function call to read file data and store into array
   readfile(in, lineCount,intArray);
   //Close file
   in.close();
   //Output file object
   ofstream out("C:/Users/deept/Desktop/reverse_output.txt");
   //Error check
   if (!out) {
       cout << "File not open!!!" << endl;
       exit(0);
   }
   //Write into file
   for (int i = lineCount - 1; i >= 0; i--) {
       out << intArray[i] << endl;
   }
   //close file
   out.close();
   cout << "Reverse write completed" << endl;
   //Free allocated memory
   delete[] intArray;  
}
//Method to find lines count
void findLineCount(ifstream& in, int &count) {
   int data;
   while (in>>data) {
       count++;
   }
}
//Method to read file
void readfile(ifstream& in, int count, int* arr) {
   for (int i = 0; i < count; i++) {
       in >>*(arr+i);
   }
}

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input file

18
9
27
5
48
16
2
53
64
98
49
82
7
17
53
38
65
71
24
31

output file

31
24
71
65
38
53
17
7
82
49
98
64
53
2
16
48
5
27
9
18