Program2-Write a program to add two number in PL/SQL

This program can be solved in many ways. So Let us understand how the add is performed
Method-1:
Suppose we have two constant value 2 and 3 .So we need the addition operator(+) to add these two numbers
Input-2 and 3
Output-5
Operation- addition so use addition operator (+)

Code-
SQL> set serveroutput on
SQL>
SQL>
SQL> Begin
  2  Dbms_output.put_line(2+3);
  3  End;
  4  /
5

PL/SQL procedure successfully completed.

SQL>


Method-2:
Suppose you want to add two values taken at run time
Input-Take two variable and store two value into it.Assume two variable are n1 and n2.
Output- addition a+b
Operation- addition (+)
Code-
SQL> declare
  2  n1 number;
  3  n2 number;
  4  Begin
  5  n1 :=2;
  6  n2 :=3;
  7  Dbms_output.put_line(n1+n2);
  8  End;
  9  /
5

PL/SQL procedure successfully completed.

SQL>



Method-3:
Take two number n1 and n2 and store it into third variable result.
Input-Take two variable and store the result into third variable result.
Output- Result of addition
Operation- addition (+)

SQL> declare
  2    n1 number;
  3    n2 number;
  4    result number;
  5    Begin
  6     n1 :=2;
  7     n2 :=3;
  8     result:=n1+n2;
  9    Dbms_output.put_line(result);
 10    End;
 11    /
5

PL/SQL procedure successfully completed.

SQL>
Method-4:
Ask user to enter two number n1 and n2 and store it into third variable result.
Input-Take two variable and store the result into third variable result.
Output- Result of addition
Operation- addition (+)

Code-
SQL> declare
  2    n1 number;
  3    n2 number;
  4    result number;
  5    Begin
  6     n1 :=&n1;
  7     n2 :=&n2;
  8     result:=n1+n2;
  9    Dbms_output.put_line(result);
 10    End;
 11    /
Enter value for n1: 10
old   6:    n1 :=&n1;
new   6:    n1 :=10;
Enter value for n2: 20
old   7:    n2 :=&n2;
new   7:    n2 :=20;
30

PL/SQL procedure successfully completed.

SQL>

Note- This program can be solved in many ways .I have taken from very basic to often used method.
I hope you can get the idea how to approach the problem to solve in real-time in PL/SQL.