How do you write a basic program find whether number is even or odd if even display its square and if odd display its cube?

Answer 1

Divide that number into 2 using modulus division. Modulus division get the remainder of the division. If it has no remainders, then it's an even number. If not, then it's an odd number. Here's a pseudo code of the program.

ALGORITHM ODD_EVEN

INPUT (number)

IF (number MOD 2 == 0) THEN

DISPLAY ("Even")

ELSE

DISPLAY ("Odd")

END IF

END ODD_EVEN

Amendment: You did ask for a BASIC program:

10 INPUT X: IF X = 999 THEN STOP

20 PRINT X;: IF X/2 = INT(X/2) THEN PRINT "EVEN" ELSE PRINT "ODD"

30 GOTO 10

Answer 2

In pseudocode:

Given value is an integer...

If the least significant bit of value is set

Then return value * value * value

Else return value * value

To determine if the least significant bit is set or not, use the bitwise AND operator. The least significant bit is 0x1, thus value AND 0x1 returns 0x1 when the bit is set, or 0x0 when the bit is not set. However, you need to be careful with signed integers because some architectures use ones complement notation while others use twos complement. With ones complement, a negative value inverts all the bits of the equivalent positive value whereas twos complement inverts the bits and then adds one. Twos complement is more common but if you're not sure of the architecture's representation of signed values or simply want your code to be portable regardless of the representation, then use the MOD (modus) operator to find the remainder after dividing by 0x2. If the result is 0x1, then the value is odd, regardless of its sign. This is less efficient than bitwise AND but if you're certain the architecture is ones complement, then all positive odd values have the least significant bit set while all negative odd values do not (including -0 which is binary 11111110 in ones complement notation). With twos complement, however, all odd values always have the least significant bit set regardless of the sign, and zero is always represented as binary 00000000 (there is no -0 in twos complement notation).