#include<iostream>
#include<string>
#include<cctype>
using namespace std;

int encrypt(int);
int decrypt(int);

int main()
{
    
    cout<<"Would you like to (e)ncrypt or (d)ecrypt? (e/d):  ";
    string choice = "";
    getline(cin, choice);
    while(choice != "e" && choice != "E" && choice != "d" && choice != "D")
    {
         cout<<"Enter a valid response please!"<<endl;
         cout<<"Would you like to (e)ncrypt or (d)ecrypt? (e/d):  ";
         getline(cin, choice);
    }
    
	if(choice == "e" || choice == "E")
	{
         string text;
         choice = "";
         cout<<"Enter the text to encrypt:  \n";

	     getline(cin, text); 
	
      	 char* pValues = new char[text.length()];

	     for(int i = 0; i < text.length(); i++)
	     {
		      pValues = int (text);
		      pValues = encrypt(pValues);
		      pValues = char (pValues);
		      cout<< pValues;
	
	     }
    }
    
    else if(choice == "d" || choice == "D")
    {
         choice = "";
         cout<<"Enter the text to decrypt:  \n";
         string text;
	     getline(cin, text); 
	
      	 char* pValues = new char[text.length()];

	     for(int i = 0; i < text.length(); i++)
	     {
		      pValues = int (text);
		      pValues = decrypt(pValues);
		      pValues = char (pValues);
		      cout<< pValues;
	     }
         
    }
    cout<<endl;
	system("pause");
	return 0;
}

int decrypt(int x)
{
    int result = 0;
    int a = 0;
    int b = 0;
    int c = 0;
    if(x >= 10 && x < 100)
	{
		a = x / 10;	
		b = x - a * 10;
		a = (a - 7) + 10;
		b = (b - 7) + 10;
		a = a * 10;
		result = a + b;
	}
     else if(x >= 100)
	{
	     a = x / 100;
		b = (x - (a*100)) / 10;
		c = (x - (a*100)) - (b*10);
		a = (a - 7) + 10;
		b = (b - 7) + 10;
		c = (c - 7) + 10;
		a = a * 100;
		b = b * 10;
		result = a + b + c;
 	}
	return result;
}

int encrypt(int x)
{
	int result = 0;
	int a = 0;
	int b = 0;
	int c = 0;
	if(x >= 10 && x < 100)
	{
		a = x / 10;	
		b = x - a * 10;
		a = (a + 7) % 10;
		b = (b + 7) % 10;
		a = a * 10;
		result = a + b;
	}
	else if(x >= 100)
	{
	     a = x / 100;
		b = (x - (a*100)) / 10;
		c = (x - (a*100)) - (b*10);
		a = (a + 7) % 10;
		b = (b + 7) % 10;
		c = (c + 7) % 10;
		a = a * 100;
		b = b * 10;
		result = a + b + c;
 	}
	return result;
}