ADA Program to find the difference of two integer number

Program

With Gnat.IO; use Gnat.IO;
procedure subtwointeger is
	a : Integer;
	b : Integer;
	diff : Integer;
begin
	Put ("Enter value of a: ");
	Get (a);
	Put ("Enter value of b: ");
	Get (b);
	diff := a - b;
	Put_Line ("Difference = " & integer'image(diff));
end;

This Ada program reads two integer numbers from the user, calculates their difference, and displays the result.

1. With Gnat.IO; use Gnat.IO;

   • Imports the Gnat.IO package for input and output functions.
   • use Gnat.IO; allows direct use of procedures like Put, Put_Line, and Get.

2. procedure subtwointeger is

   • Defines the procedure subtwointeger, which is the main program.

3. Variable Declarations:

   a : Integer;
   b : Integer;
   diff : Integer;
   

   • Declares three integer variables:
     • a → First number
     • b → Second number
     • diff → Stores the difference between a and b

4. begin

   • Marks the beginning of the executable code.

5. Taking User Input:

   Put ("Enter value of a: ");
   Get (a);
   Put ("Enter value of b: ");
   Get (b);
   

   • Prompts the user to enter two integer values.
   • Uses Get(a); and Get(b); to store values in a and b.

6. Calculating Difference:

   diff := a - b;
   

   • Subtracts b from a and stores the result in diff.

7. Displaying the Result:

   Put_Line ("Difference = " & integer'image(diff));
   

   • integer'image(diff) converts the integer diff into a string.
   • Put_Line prints the result to the console.

8. end;

   • Marks the end of the program.

Key Features:

• Uses Gnat.IO for input and output operations.
• Takes two integer inputs and computes their difference.
• Displays the result using integer'image(diff) for correct formatting.

Output

$ gnat make subtwointeger.adb
gcc -c subtwointeger.adb
gnatbind -x subtwointeger.ali
gnatlink subtwointeger.ali
$ ./subtwointeger
Enter value of a: 76
Enter value of b: 13
Difference =  63