Question

Write a C++ program to perform the addition of two hexadecimal numerals each with up to 10 digits. If the result of the addition is more than 10 digits long, then simply give the output message "Addition overflow" and not the result of the addition.

Use arrays to store hexadecimal numerals as arrays of characters.

Input Notes: The program reads two strings, each a sequence of hex digits (no lowercase, however) terminated by a "q". Example: 111q AAAq

Output Notes (Prompts and Labels): Each hex input string is prompted for by:

Enter a hexadecimal number of 10 or fewer hex digits

Type q to stop the entry of the hex digits

The output consists of a display of two 10-digit hex numbers being added as follows:

§0000xxxxxx

+0000000yyy

-----------------

§0000zzzzzz

where § signifies a SPACE. Note the mandatory presence of the leading zeros. Here the input values typed were "xxxxxx" and "yyy" and the result was "zzzzzz".

Answer 1

#include <iostream>
#include <string>

using namespace std;

string plus_hex(string hex1, string hex2)
{
if (hex1.length() < hex2.length())
hex1.swap(hex2);

  

/*Strat algorithm*/

int length1, length2;
length1 = hex1.length();
length2 = hex2.length();
int flag = 0; // carry
int get1, get2;
int sum;

while (length1>0)
{
//get first number
if (hex1[length1 - 1] >= 'A')
get1 = hex1[length1 - 1] - 55;
else
get1 = hex1[length1 - 1] - '0';

//get second number

if (length2 > 0)
{
if (hex2[length2 - 1] >= 'A')
get2 = hex2[length2 - 1] - 55;
else
get2 = hex2[length2 - 1] - '0';
}
else
get2 = 0;

//get the sum
sum = get1 + get2 + flag;

if (sum >= 16)
{
int left = sum % 16;
if (left >= 10)
hex1[length1 - 1] = 'A' + left % 10;
else
hex1[length1 - 1] = '0' + left;
flag = 1;
}
else
{
if (sum >= 10)
hex1[length1 - 1] = 'A' + sum % 10;
else
hex1[length1 - 1] = '0' + sum;
flag = 0;
}

length1--;
length2--;
}

if (flag == 1)
return "1" + hex1;
else
return hex1;

/*End of algorithm*/
}
int main(void)
{
string hex1, hex2,hex3;
int len;
  
   cout<<"Enter 1st hexadecimal number of 10 or fewer hex digits"<<endl;
   cout<<"Type q to stop the entry of the hex digits"<<endl;
   getline(cin,hex1,'q');
   cout<<"Your 1st hexadecimal number is"<<hex1<<endl;
  
   cout<<"Enter 2nd hexadecimal number of 10 or fewer hex digits"<<endl;
   cout<<"Type q to stop the entry of the hex digits"<<endl;
   getline(cin,hex2,'q');
   cout<<"Your 2nd hexadecimal number is"<<hex2<<endl;

hex3=plus_hex(hex1, hex2);
   cout<<"Addition of above two number is"<<hex3<<endl;
   len=hex3.length();
   //cout<<len;
   if(len>10)
       cout<<"Addition Overtflow";
return 0;
}

Output:

Thank you.