从一个 class 访问成员 function 的数据成员到另一个类的成员 function

Question

When I run the code it gives

    error: 'passArray' was not declared in this scope
    cout << passArray[2];
            ^~~~~~~~~

So I want to access that character array and modify the array. For example user input is last (in string p ) then it will be converted into character array( passArray ). Then void convert() function should modify passArray[0] which is letter l to letter f and give the output as fast . Like this I want to modify many letters at once as l to f , a to e , s to l , t to t final word would be felt from the word last .

Here is the code:

#include <bits/stdc++.h>
using namespace std;

class PasswordConverter {
protected:
    string p;
    int length;
public:
    void getPassword() {
        cout << "Enter password to convert into strong one: ";
        cin >> p;
        length = p.length();
    }
    void show() {
        cout << p << endl;
        cout << length << endl;
    }
};
class strToarr : public PasswordConverter {
public:
    void typeCast() {
        char passArray[length + 1];
        strcpy(passArray, p.c_str());
    }
};
class Convert : public strToarr {
public:
    void convert() {
        cout << passArray[2];
    }
};
int main(int argc, char const *argv[]) {
    Convert strong;
    strong.getPassword();
    strong.show();
    strong.typeCast();
    strong.convert();
    return 0;
}

Answer 1

I've tried to fix and simplify the code. I believe there is no need for any classes, just keep it simple with ordinary functions.

Also please not that std::string already has operator[] so the extra array is not necessary to edit the string but I kept it there if you need it.

// Do NOT use this, don't be lazy and include the proper headers
//#include <bits/stdc++.h>
#include <iostream>
#include <string>
#include <vector>
// Also do not use this, at least not in headers
//using namespace std;


std::string getPassword() {
    std::string p;
    std::cout << "Enter password to convert into strong one: ";
    std::cin >> p;
    return p;
}

void show_password(const std::string& password) {
    // Do not use 'endl' for newlines, sadly it also flushes the buffer 
    // making it slow.
    std::cout << password << '\n';
    std::cout << password.size() << '\n';
}
std::vector<char> typeCast(const std::string& p) {
    auto begin = p.c_str();
    std::vector<char> p_array{begin,begin+p.size()+1};
    return p_array;
}

void convert(const std::vector<char>& passArray) {
    std::cout << passArray[2];
}

int main(int argc, char const *argv[]) {
    auto pass = getPassword();
    show_password(pass);
    auto pass_array = typeCast(pass);
    convert(pass_array);
    return 0;
}