# Sum of the first and last digit of a number in PL/SQL

Prerequisite PL/SQL introduction
In PL/SQL code groups of commands are arranged within a block. A block group related declarations or statements. In declare part, we declare variables and between begin and end part, we perform the operations.

Given a number n, the task is to find the sum of its first and last digit.
Examples:

```Input: 14598.
Output: Sum of the first and last digit is 9.

Input: 987456.
Output: Sum of the first and last digit is 15.
```

Approach is to use the substr() function and store the first and last digit and then print their sum.

Below is the required implementation:

 `DECLARE`  `    ``-- declare variables are A, B,  C and S ` `    ``-- these are same datatype integer ` `    ``a ``INTEGER` `:= 14598;  ` `    ``b ``INTEGER` `:= 0;  ` `    ``C ``INTEGER` `:= 0;  ` `    ``s ``INTEGER``;  ` `BEGIN`  `    ``IF a > 9 ``THEN`  `      ``c := Substr(a, 1, 1);  ` ` `  `      ``b := Substr(a, Length(a), 1);  ` ` `  `      ``s := b + c;  ` `    ``ELSE`  `      ``s := a;  ` `    ``END` `IF;  ` ` `  `    ``dbms_output.Put_line(``'Sum of the first and last digit is '`  `                         ``||s);  ` `END``;  ` `-- Program End  `

Output:

```Sum of the first and last digit is 9
```

## tags:

SQL SQL-PL/SQL SQL