lab 2.4 c++

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

int choiceCheck() {
    int choice;
    bool isIncorrect;
    do {
        isIncorrect = true;
        cin >> choice;
        if (cin.fail() || (cin.get() != '\n')) {
            cout << "Error! Input a number" << endl;
            cin.clear();
            while (cin.get() != '\n');
        } else {
            cin.clear();
            if (choice > 0 && choice < 3) {
                isIncorrect = false;
            } else {
                cout << "Error! Input 1 or 2" << endl;
            }
        }

    } while (isIncorrect);
    return choice;
}

int inputCheck() {
    bool isIncorrect;
    int n;
    cout << "Input n" << endl;
    do {

        isIncorrect = true;
        cin >> n;
        if (cin.fail() || (cin.get() != '\n')) {
            cout << "Error! Input a number" << endl;
            cin.clear();
            while (cin.get() != '\n');
        } else {
            cin.clear();
            if (n > 1) {
                isIncorrect = false;
            } else {
                cout << "Error! Input a number greater than 1" << endl;
            }
        }
    } while (isIncorrect);
    return n;
}

int *inputCheckArray(int n, int *arr) {
    int i;
    bool isIncorrect;
    for (i = 0; i < n; i++) {
        do {
            isIncorrect = true;
            cin >> arr[i];
            if (cin.fail() || (cin.get() != '\n')) {
                cout << "Error! Input a number" << endl;
                cin.clear();
                while (cin.get() != '\n');
            } else {
                isIncorrect = false;
            }
        } while (isIncorrect);
    }
    return arr;
}

string checkInputFilePath() {
    string path;
    bool isInCorrect;
    do {
        cout << "Input path to the file:\n";
        isInCorrect = false;
        cin >> path;
        ifstream fin(path);
        if (!fin.is_open()) {
            cout << "Could not open the file" << endl;
            isInCorrect = true;
        } else {
            fin.close();
        }

    } while (isInCorrect);
    return path;
}


int *fileCheckArray(int &n, int *arr) {
    string path;
    bool isIncorrect;
    int i;
    do {
        path = checkInputFilePath();
        ifstream fin(path);
        isIncorrect = false;
        fin >> n;
        if (fin.fail()) {
            cout << "The data is incorrect" << endl;
            isIncorrect = true;
        }
        if (!isIncorrect && (n < 2)) {
            cout << "The data is incorrect" << endl;
            isIncorrect = true;
        }
        if (!isIncorrect) {
            arr = new int [n];
            for (i = 0; i < n; i++) {
                fin >> arr[i];
                if (fin.fail()) {
                    cout << "The data is incorrect" << endl;
                    isIncorrect = true;
                }
            }
            if (!fin.eof()) {
                cout << "The data is incorrect" << endl;
                isIncorrect = true;
            }
        }
        fin.close();
    } while (isIncorrect);
    return arr;
}


int *inputChoice(int &n, int *arr) {
    int choice;

    cout << "Choose input option:\n1.Input through console\n2.Input through file" << endl;
    choice = choiceCheck();
    if (choice == 1) {
        n = inputCheck();
        arr = new int[n];
        arr = inputCheckArray(n, arr);
    } else {
        arr = fileCheckArray(n, arr);
    }
    return arr;
}

int *sum(int n, int *arr, int *sumArr) {
    int i;
    for (i = 0; i < n; i++) {
        sumArr[i] = arr[i] + arr[i + 1];
    }
    return sumArr;
}

int findMax(int n, int *sumArr) {
    int max, i;
    max = sumArr[0];
    for (i = 0; i < n; i++) {
        if (sumArr[i] > max) {
            max = sumArr[i];
        }
    }
    return max;
}


string checkOutputFilePath() {
    string path;
    bool isIncorrect;
    cout
            << "Input file path and the name of the file for\nexample С:\\Projects\\Number\\FileName.txt. If the\nfile does not exist, then it will be created\nautomatically in the root folder of the program:\n";
    isIncorrect = false;
    cin >> path;
    ifstream fin(path);
    if (!fin.is_open()) {
        cout << "Could not open the file or it does not exist" << endl;
        isIncorrect = true;
    } else {
        fin.close();
    }
    if (isIncorrect) {
        cout << "File will be created in the root folder of the program\n";
        path = "Result.txt";
    }
    return path;
}

void outputMax(int max) {
    cout << max << endl;
}

void outputFile(int max) {
    string path;
    path = checkOutputFilePath();
    ofstream fout(path);
    fout << max << endl;
    fout.close();
}

void outputChoice(int &max) {
    int choice;
    cout << "Choose output option:\n1.Output through console\n2.Output through file" << endl;
    choice = choiceCheck();
    if (choice == 1) {
        outputMax(max);
    } else {
        outputFile(max);
    }
}


int main() {
    int n, max;
    int *arr;
    int *sumArr;
    arr = inputChoice(n, arr);
    n--;
    sumArr = new int[n];
    sumArr = sum(n, arr, sumArr);
    max = findMax(n, sumArr);
    outputChoice(max);
    return 0;
}