*Write a program in QBasic to check if the input number is even or odd.*

**Program using IF..ELSE**

```
CLS
INPUT "Enter a Number: ", n
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END
```

**Program using only IF**

```
CLS
INPUT "Enter a Number: ", n
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
END IF
IF n MOD 2 = 1 THEN
PRINT "Input Number is Odd"
END IF
END
```

**Program using Select Case**

```
CLS
INPUT "Enter a Number: ", n
SELECT CASE (n MOD 2)
CASE 1
PRINT "Input Number is Odd"
CASE 0
PRINT "Input Number is EVEN"
END SELECT
END
```

**Program using subroutine**

```
DECLARE SUB odd_even
CLS
odd_even
END
SUB odd_even
INPUT "Enter a Number: ", n
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END SUB
```

**Program using subroutine – Passing input as an argument**

```
DECLARE SUB odd_even(n)
CLS
INPUT "Enter a Number: ", n
odd_even(n)
END
SUB odd_even(n)
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END SUB
```

**Program using Function**

```
DECLARE FUNCTION odd_even()
CLS
odd_even()
END
FUNCTION odd_even()
INPUT "Enter a Number: ", n
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END FUNCTION
```

**Program using Function – Passing input as an argument**

```
DECLARE FUNCTION odd_even(n AS INTEGER)
CLS
INPUT "Enter a Number: ", n
r = odd_even(n)
END
FUNCTION odd_even(n AS INTEGER)
IF n MOD 2 = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END FUNCTION
```

**Program using Function – Passing input as an argument and returning True/False**

```
DECLARE FUNCTION odd(n AS INTEGER)
CLS
INPUT "Enter a Number: ", n
r = odd(n)
IF r = 0 THEN
PRINT "Input Number is Even"
ELSE
PRINT "Input Number is Odd"
END IF
END
FUNCTION odd(n AS INTEGER)
odd = n MOD 2
END FUNCTION
```

*0 is considered as false and 1 is considered as true.*

**Read**