I need to write a c++ program with these objectives - c++

Question

A C++ program which read data from a text file. Suppose text file contains a
paragraph about any topic. Your program asks user to enter file name without extension. Now, a
user defined function (name: ReadWordByWord()) reads all data word by word and store in a
character type array with dynamically grows according to the data.
Finally, declare a user-defined function (name: SaveInReverse()) which stores this text into a
text file (name is entered by user) in reverse order of words e.g. last words will be stored at start,
then 2nd last word, 3rd last word etc. of the original document.
And here is what I've done so far... Here I am not using the delete command, that if I use will cause an error- a heap error. How can I accomplish that first? And then what are any tips to improve this program.
#include<iostream>
#include<string>
#include<fstream>
using namespace std;
char* readWordByWord(char * old)
{
int coun = 0;
for (int i = 0; old[i] != '\0'; i++) // to find the length of word
{
coun++;
}
char *newArr = new char[coun + 1];
strcpy(newArr, old);
//delete[]old; // this is where i am putting delete command to delete the previous i.e old array and then return the new one
return newArr;
}
int size = 100;
int main()
{
fstream fin;
string forCopy[1000];
int index = 0;
fin.open("file.txt");
char *p = new char[size];
while (fin >> p)
{
p = readWordByWord(p);
//cout << p<<endl;
forCopy[index++] = p;
/*for (int i = 0; p[i] != '\0'; i++)
{
}*/
}
for (int i = index - 1; i > 0; i--)
cout << forCopy[i] << " ";
delete[]p;
p = NULL;
fin.close();
return 0;
}

Answer 1

I've made it from start again (must not include newlines since only a paragraph required):
#include <iostream>
#include <fstream>
#include <string>
void reverse(char *begin, char *end) { // reverses a word
char temp;
while (begin < end) {
temp = *begin;
*begin++ = *end;
*end-- = temp;
}
}
void reverseParagraph(char *arg) { // reverses each word of the paragraph
char *word_begin = arg;
char *temp = arg;
while (*temp) {
temp++;
if (*temp == '\0')
reverse(word_begin, temp - 1);
else if (*temp == ' ') {
reverse(word_begin, temp - 1);
word_begin = temp + 1;
}
}
reverse(arg, temp - 1);
}
int main() {
std::ifstream file("file.txt");
std::string fileData = "";
while(getline(file, fileData)); // counting the number of letters for memory allocation
size_t len = fileData.length();
char *str = new char[len + 1];
strcpy(str, fileData.c_str());
reverseParagraph(str); // reverse the entire character pointer
std::cout << str << std::endl; // displays for testing
std::ofstream fileOut("out.txt");
fileOut << str << std::endl; // saving the output into another file
fileOut.close();
delete[] str;
file.close();
return 0;
}
This program firstly gets the containing data of a file and then assigns into a variable. The variable is then converted into character (pointer) after getting the string length.
After that, it recursively reverses the position each word of the fileData and finally it displays. The modified data is thereafter printed into another file.