In this program that I have written so far I am attempting to add two very large integers together using arrays:

Code:

#include <iostream>
using namespace std;
const int Size = 20;
int main ()
{
char FirstNumber [Size];
char SecondNumber [Size];
int Length;
int Length2;
int Num1 [Size];
int Num2 [Size];
int Answer [Size];
//getting numbers into character array
cout<<"Enter the First Number : ";
cin>>FirstNumber;
cout<<"Enter the Second Number : ";
cin>>SecondNumber;
//finding length of the arrays
Length = strlen (FirstNumber);
Length2 = strlen (SecondNumber);
//bringing numbers in reverse so that they can be added
for (int a = Length - 1; a >= 0; a--)
{
Num1 [a] = FirstNumber [a] - int ('0');//changing char to int
for (int a = Length2 -1; a >= 0; a--)
{
Num2 [a] = SecondNumber [a] - int ('0');
}
Answer [a] = Num1 [a] + Num2 [a];//getting sum of two numbers in the arrays
if (Answer [a] > 10)//if answer of the two numbers is greter than ten, minus 10 and add ten to the next number
{
Answer [a] = Answer [a] - 10;
Answer [a--] = Answer [a--] + 1;
}
cout<< Answer [a];
}
return 0;
}

Everything works right untill the numbers add up to be bigger then 10 and then I am trying to figure out how to carry the one to the next number. Any suggestions?