Homework extremel programming

//
//  main.cpp
//  Project 2
//
//  Created by Артур Макушев on 21/02/2019.
//  Copyright © 2019 Артур Макушев. All rights reserved.
//

#include <iostream>
#include <map>
#include <cstring>
#include <cmath>
using namespace std;

int multiplication (int a, int b, char c){
    int result = a*b;
    cout <<a << c << b <<" = ";
    return result;

}
int subtraction (int a, int b, char c){
    int result = a-b;
    cout <<a << c << b <<" = ";
    return result;
}
int addition (int a, int b, char c){
    int result = a+b;
    cout <<a << c << b <<" = ";
    return result;
}
int main() {
        map <int, string> words;
        //words [0] = "zero";
        words [1] = "one";
        words [2] = "two";
        words [3] = "three";
        words [4] = "four";
        words [5] = "five";
        words [6] = "six";
        words [7] = "seven";
        words [8] = "eight";
        words [9] = "nine";
        words [10] = "ten";
        words [11] = "eleven";
        words [12] = "twelve";
        words [13] = "thirteen";
        words [14] = "fourteen";
        words [15] = "fifteen";
        words [16] = "sixteen";
        words [17] = "seventeen";
        words [18] = "eighteen";
        words [19] = "nineteen";
        words [20] = "twenty";
        words [30] = "thirty";
        words [40] = "fourty";
        words [50] = "fifty";
        words [60] = "sixty";
        words [70] = "seventy";
        words [80] = "eighty";
        words [90] = "ninety";
        words [100] = "hundred";
        words [1000] = "thousand";
        words [1000000] = "million";
        words [1000000000] = "billion";
        int a,b,result,rememberR,rememberB,rememberC;
        int n = 1;
        int powerB;
        int power = -1;
        char c;
    cout << "Введите числа и действие"<<endl;
        cin >> a >> c >> b;
    if (c == 43 ){
       result =  addition(a,b,c);
        rememberC = result;
        while (result!=0){
            result = result/10;
            power+=1;
        }
        result = rememberC;
        powerB = power%3;
        power = power-powerB;
        cout << result<<endl;
        while (power>=0){
        if (result >= pow(10,power)){
            result = result / pow (10,power);
        }
        rememberR = result%100;

        if (result >=100){
        cout << words[result/100]<<" ";
        cout << words [100]<<" ";
        }
        result = rememberR;
        if (result > 20&& result <100){
            cout << words[(result/10)*10]<<" ";
            cout << words[result%10]<<" ";
        }
        if (result < 21){
            cout << words[result]<<" ";
        }
            if (power!=0){
                cout << words[pow(10,power)]<<" ";}
            rememberR = 0;
            n=0;
            while (rememberR!=power){
                rememberR+=1;
                n = n *10;
            }

        power = power-3;
        result = rememberC;

            result = result%n;
        }



    }

    if (c == 42 ){
        result =multiplication(a,b,c);
        cout << result<<endl;
        rememberC = result;
        while (result!=0){
            result = result/10;
            power+=1;
        }
        result = rememberC;
        powerB = power%3;
        power = power-powerB;
        cout << result<<endl;
        while (power>=0&&result!=0){
            rememberC;
            if (result >= pow(10,power)){
                result = result / pow (10,power);
            }
            rememberR = result%100;

            if (result >=100){
                cout << words[result/100]<<" ";
                cout << words [100]<<" ";
            }
            result = rememberR;
            if (result > 20&& result <100){
                cout << words[(result/10)*10]<<" ";
                cout << words[result%10]<<" ";
            }
            if (result < 21){
                cout << words[result]<<" ";
            }
            if (power!=0){
                cout << words[pow(10,power)]<<" ";}
            rememberR = 0;

            while (rememberR!=power){
                rememberR+=1;
                n = n *10;
            }

            power = power-3;
            result = rememberC;
            rememberC = (rememberC/n)*n;

            result = result- rememberC;
            n=1;

           // cout << endl << "result = "<< result<<endl;
        }



    }
    if (c == 45 ){
        result =subtraction(a,b,c);
        cout << result<<endl;
        rememberC = result;
        while (result!=0){
            result = result/10;
            power+=1;
        }
        result = rememberC;
        powerB = power%3;
        power = power-powerB;
        cout << result<<endl;
        while (power>=0){
            if (result >= pow(10,power)){
                result = result / pow (10,power);
            }
            rememberR = result%100;

            if (result >=100){
                cout << words[result/100]<<" ";
                cout << words [100]<<" ";
            }
            result = rememberR;
            if (result > 20&& result <100){
                cout << words[(result/10)*10]<<" ";
                cout << words[result%10]<<" ";
            }
            if (result < 21){
                cout << words[result]<<" ";
            }
            if (power!=0){
                cout << words[pow(10,power)]<<" ";}
            rememberR = 0;
            while (rememberR!=power){
                rememberR+=1;
                n = n *10;
            }

            power = power-3;
            result = rememberC;

            result = result%n;
        }



    }

    return 0;
}