Unscrambling words in C++ using pointers - c++

Question

for my csc 102 class I have to create a program that will replace certain letters with others in a text file. The file holds five words and I have to use a class system. This sounds simple enough to me, but my variables in the class have to be pointer variables. Being that all of my classes are online now, trying to use my professors handwritten notes on canvas is all I have to explain how he wants projects done. I sort of understand what a pointer is. The pointer holds the address of a value. You have to dereference it with * to get the value stored there. However, I just don't see how pointers are to be used in this problem. This is the first prompt out of four and I just don't get what i'm supposed to do with the pointers. I will attach my code below and what the prompt asks me to do. I appreciate any help.
Prompt:
Problem 1: A computer keyboard has defect (like speech defect in humans) in reading for ‘p’ /’P’ as ‘f’/’F’ or vice versa and ‘n’/’N’ as ‘l’/’L’ or vice versa
Create a class with pointer variables that would correct the spelling of each word from the input.txt print them in in an output.txt.
Class Header file:
#pragma once
#include<iostream>
#include<fstream>
#include<string>
using namespace std;
class keyfix
{
char* input;
char* output;
string* word;
char* wordarray[10];
public:
keyfix();
~keyfix();
void readfile(ifstream&);
void correctspelling(ofstream&);
void outputfile();
void print()const;
};
class implementation file:
#include "keyfix.h"
keyfix::keyfix() {
input = new char;
output = new char;
*input = 'o';
*output = 'o';
word = new string;
*word = "empty";
*wordarray = new char;
}
keyfix::~keyfix() {
delete input;
delete output;
delete word;
input = output = NULL;
word = NULL;
}
void keyfix::readfile(ifstream& a) {
for (int i = 0; i < 10; i++) {
a >> wordarray[i];
}
}
I have an ifstream object and an ofstream object in main.
In my mind, I planned to use a character array instead of a string so that I could change each incorrect letter without using functions we haven't yet covered like anything in <algorithms>. I am in real need of some direction here. I am sure some of y'all can look at my code and tell, but I get a nullptr error whenever I try to test the read file function.
EDIT: I am now writing it with wordarray as a plain char array. It may be accepted this way, it may not be.
Also, the size is 10 because the file is provided and the largest word only has 10 letters.

Answer 1

As recommended in the comments, I wrote the program without pointers, and then changed a variable to a pointer type in my class. Here is the final project for any future students who happen to have this exact problem. (I saw the problem on chegg so I know he uses it commonly)
#pragma once
#include<iostream>
#include<fstream>
#include<string>
using namespace std;
class keyfix
{
char* input;
char wordarray[10];
public:
keyfix();
~keyfix();
void readfile(ifstream&);
void correctspelling(ofstream&);
void print()const;
};
#include "keyfix.h"
keyfix::keyfix() {
input = new char;
*input = 'o';
wordarray[10];
}
keyfix::~keyfix() {
delete input;
input = NULL;
}
void keyfix::readfile(ifstream& a) {
for (int i = 0; i < 10; i++) {
wordarray[i] = NULL;
}
a >> wordarray;
}
void keyfix::correctspelling(ofstream& b) {
for (int index = 0; index < 10; index++) {
*input = wordarray[index];
if (*input == 'f') {
wordarray[index] = 'p';
}
else if (*input == 'F') {
wordarray[index] = 'P';
}
else if (*input == 'p') {
wordarray[index] = 'f';
}
else if (*input == 'P') {
wordarray[index] = 'F';
}
else if (*input == 'n') {
wordarray[index] = 'l';
}
else if (*input == 'N') {
wordarray[index] = 'L';
}
else if (*input == 'l') {
wordarray[index] = 'n';
}
else if (*input == 'L') {
wordarray[index] = 'N';
}
b << wordarray[index];
}
b << endl;
}
void keyfix::print()const {
for (int i = 0; i < 10; i++) {
cout << wordarray[i];
}
cout << endl;
}
#include"keyfix.h"
//if input is f or F, output p or P
//if input is n or N, output l or L
//if input is p or P, output f or F
//if input is l or L, output n or N
int main() {
ifstream infile;
infile.open("input.txt");
ofstream outfile;
outfile.open("output.txt");
keyfix object;
for (int i = 0; i < 5; i++) {
object.readfile(infile);
object.correctspelling(outfile);
object.print();
}
}