How to check number is even or odd

Help and Feedback Scripting Support
#1

This is my code to check if a number is even or odd

local number = 1

if number == 1 then 
	print("number is odd")
elseif number == 2 then 
	print("number is even")
elseif number == 3 then 
	print("number is odd")
elseif number == 4 then 
	print("number is even")
elseif number == 5 then 
	print("number is odd")
elseif number == 6 then 
	print("number is even")
elseif number == 7 then 
	print("number is odd")
elseif number == 8 then 
	print("number is even")
elseif number == 9 then 
	print("number is odd")
elseif number == 10 then 
	print("number is even")
elseif number == 11 then 
	print("number is odd")
elseif number == 12 then 
	print("number is even")
elseif number == 13 then 
	print("number is odd")
elseif number == 14 then 
	print("number is even")
elseif number == 15 then 
	print("number is odd")
elseif number == 16 then 
	print("number is even")
elseif number == 17 then 
	print("number is odd")
elseif number == 18 then 
	print("number is even")
elseif number == 19 then 
	print("number is odd")
elseif number == 20 then 
	print("number is even")
elseif number == 21 then 
	print("number is odd")
elseif number == 22 then 
	print("number is even")
elseif number == 23 then 
	print("number is odd")
elseif number == 24 then 
	print("number is even")
elseif number == 25 then 
	print("number is odd")
elseif number == 26 then 
	print("number is even")
elseif number == 27 then 
	print("number is odd")
elseif number == 28 then 
	print("number is even")
elseif number == 29 then 
	print("number is odd")
elseif number == 30 then 
	print("number is even")
elseif number == 31 then 
	print("number is odd")
elseif number == 32 then 
	print("number is even")
elseif number == 33 then 
	print("number is odd")
elseif number == 34 then 
	print("number is even")
elseif number == 35 then 
	print("number is odd")
elseif number == 36 then 
	print("number is even")
elseif number == 37 then 
	print("number is odd")
elseif number == 38 then 
	print("number is even")
elseif number == 39 then 
	print("number is odd")
elseif number == 40 then 
	print("number is even")
elseif number == 41 then 
	print("number is odd")
elseif number == 42 then 
	print("number is even")
elseif number == 43 then 
	print("number is odd")
elseif number == 44 then 
	print("number is even")
elseif number == 45 then 
	print("number is odd")
elseif number == 46 then 
	print("number is even")
elseif number == 47 then 
	print("number is odd")
elseif number == 48 then 
	print("number is even")
elseif number == 49 then 
	print("number is odd")
elseif number == 50 then 
	print("number is even")
elseif number == 51 then 
	print("number is odd")
elseif number == 52 then 
	print("number is even")
elseif number == 53 then 
	print("number is odd")
elseif number == 54 then 
	print("number is even")
elseif number == 55 then 
	print("number is odd")
elseif number == 56 then 
	print("number is even")
elseif number == 57 then 
	print("number is odd")
elseif number == 58 then 
	print("number is even")
elseif number == 59 then 
	print("number is odd")
elseif number == 60 then 
	print("number is even")
elseif number == 61 then 
	print("number is odd")
elseif number == 62 then 
	print("number is even")
elseif number == 63 then 
	print("number is odd")
elseif number == 64 then 
	print("number is even")
elseif number == 65 then 
	print("number is odd")
elseif number == 66 then 
	print("number is even")
elseif number == 67 then 
	print("number is odd")
elseif number == 68 then 
	print("number is even")
elseif number == 69 then 
	print("number is odd")
elseif number == 70 then 
	print("number is even")
elseif number == 71 then 
	print("number is odd")
elseif number == 72 then 
	print("number is even")
elseif number == 73 then 
	print("number is odd")
elseif number == 74 then 
	print("number is even")
elseif number == 75 then 
	print("number is odd")
elseif number == 76 then 
	print("number is even")
elseif number == 77 then 
	print("number is odd")
elseif number == 78 then 
	print("number is even")
elseif number == 79 then 
	print("number is odd")
elseif number == 80 then 
	print("number is even")
elseif number == 81 then 
	print("number is odd")
elseif number == 82 then 
	print("number is even")
elseif number == 83 then 
	print("number is odd")
elseif number == 84 then 
	print("number is even")
elseif number == 85 then 
	print("number is odd")
elseif number == 86 then 
	print("number is even")
elseif number == 87 then 
	print("number is odd")
elseif number == 88 then 
	print("number is even")
elseif number == 89 then 
	print("number is odd")
elseif number == 90 then 
	print("number is even")
elseif number == 91 then 
	print("number is odd")
elseif number == 92 then 
	print("number is even")
elseif number == 93 then 
	print("number is odd")
elseif number == 94 then 
	print("number is even")
elseif number == 95 then 
	print("number is odd")
elseif number == 96 then 
	print("number is even")
elseif number == 97 then 
	print("number is odd")
elseif number == 98 then 
	print("number is even")
elseif number == 99 then 
	print("number is odd")
elseif number == 100 then 
	print("number is even")
end
3 Likes
#2

If you were to continue this you would have an endless script so instead I would use this

Here is an example:

local a = 20 --This would be the number you are checking

if 20%2 ==  0 then 
Print("Even")
else
Print("odd") 
end
8 Likes
#3

Check to see if the number is perfectly divisible by 2.

1 Like
#4

Yeah so to put it Simply, You use Modulus ( % ) to Check if its even or odd

Modulus is Like Division, except it returns the remainder

local x = 3 -- Our Number
if x % 2 == 0 then -- Checks if there is no remainder, in this case, returns 1 so odd
print("even") -- If Equation Returns 0
else
print("odd") -- If Equation Returns 1
end

My Source

Arithmetic Operators:

Integer: A Whole Number
(Ex: 15)

Float: A Number with a Decimal
(Ex 3.14159265359...)

+ Addition: Adds a Integer of Float

- Subtraction: Subtacts a Integer or Float

* Multiplication: Multiplies a Integer or Float

/ Division: Divides a Integer or Float (No Remainder)

^ Exponent: returns the Integer or Float to the Power of x
(Ex: 3^2 Is Equivalent to 3 * 3 which equals 9)

% Modulus: Divides a Integer or Float and returns the Remainder

<Var> Negation: returns the Opposite Value of a Variable (only with Integers or Floats)
Ex:

local Apples = 100
print(-Apples) -- Prints "-100" due to the negative sign being added to it

Also my Source on certain Arithmetic Operators

7 Likes
#5

Your solution is pretty inefficient, if you want to go further than a 100 numbers, here’s what I suggest you use.

This solution will let you check if numbers are even or odd until 1000 for example, however you can try any number as the argument.

local function checkIfNumbersAreEvenOrOdd(Until)
    
    local SourceCode = "local number = 1\n"
    local Even = false

    for i = 1, Until do

        if i == 1 then
            SourceCode = SourceCode..string.format("if number == %s then",i).."\n"
        else
            SourceCode = SourceCode..string.format("elseif number == %s then",i).."\n"
        end

        if Even then

            SourceCode = SourceCode..[[  print("number is even")]].."\n"
        else

            SourceCode = SourceCode..[[  print("number is odd")]].."\n"
        end

        Even = not Even
    end

    SourceCode = SourceCode.."end"

    return SourceCode
end

print(checkIfNumbersAreEvenOrOdd(1000))
3 Likes
#6

This is unnecessary, the Modulus here divides by 2, if you have 1000, it will return 0, normal division would be 500, if you have 1001, it will return 1, which is odd

I tested the code, i know it works

If anything, this code is unnecessary for a simple equation / number check

3 Likes
#7

Yea But You Can Just Call The Function With 1001 As Argument!

1 Like
#8

like i said, unnecessary

print(1001 % 2) -- 1, Odd

print(1002 % 2) -- 0, Even (No remainder)

Only one singular line of code is needed to check if its even or odd

Even in a loop, its still correct:

local Number = 0


while wait() do
	if Number % 2 == 0 then
		print("even")
	else
		print("odd")
	end
	Number += 1
end
4 Likes
#9

Oh Wow, That’s an Awesome Solution, This Whole Time I was Using my method, Thanks man.

2 Likes
#10

Um…no. To actually check, do a division modulo 2 operation.

local function checkEven(x)
	if x % 2 == 0 then
		return true
	end
	return false
end

If you are using 32-bit integers, an alternative way is this:

local function bit32even(x)
	if bit32.band(x, 0x00000001) == 0 then
		return true
	end
	return false
end

The way that this works is that it masks off all but the least significant bit (the 1’s position). If that bit is set (1), then the number is odd. If that bit is not set (0), then it’s even.

Hope this helps.

1 Like
#11

Same thing, unless you are talking to the other person

Interesting.

erogke4orgklerg

#12

That second method only works on integers. For me coming for a C/Assembler background, it’s a simple AND instruction on the CPU. Besides, coding at that level, everything is integer. You learn how to do bit manipulation really quick.

1 Like
#13

Wayyyy too small , only goes up to 100!

here’s an improved version

if number == 1 then
        print("number is odd")
elseif number == 2 then
        print("number is even")
elseif number == 3 then
        print("number is odd")
elseif number == 4 then
        print("number is even")
elseif number == 5 then
        print("number is odd")
elseif number == 6 then
        print("number is even")
elseif number == 7 then
        print("number is odd")
elseif number == 8 then
        print("number is even")
elseif number == 9 then
        print("number is odd")
elseif number == 10 then
        print("number is even")
elseif number == 11 then
        print("number is odd")
elseif number == 12 then
        print("number is even")
elseif number == 13 then
        print("number is odd")
elseif number == 14 then
        print("number is even")
elseif number == 15 then
        print("number is odd")
elseif number == 16 then
        print("number is even")
elseif number == 17 then
        print("number is odd")
elseif number == 18 then
        print("number is even")
elseif number == 19 then
        print("number is odd")
elseif number == 20 then
        print("number is even")
elseif number == 21 then
        print("number is odd")
elseif number == 22 then
        print("number is even")
elseif number == 23 then
        print("number is odd")
elseif number == 24 then
        print("number is even")
elseif number == 25 then
        print("number is odd")
elseif number == 26 then
        print("number is even")
elseif number == 27 then
        print("number is odd")
elseif number == 28 then
        print("number is even")
elseif number == 29 then
        print("number is odd")
elseif number == 30 then
        print("number is even")
elseif number == 31 then
        print("number is odd")
elseif number == 32 then
        print("number is even")
elseif number == 33 then
        print("number is odd")
elseif number == 34 then
        print("number is even")
elseif number == 35 then
        print("number is odd")
elseif number == 36 then
        print("number is even")
elseif number == 37 then
        print("number is odd")
elseif number == 38 then
        print("number is even")
elseif number == 39 then
        print("number is odd")
elseif number == 40 then
        print("number is even")
elseif number == 41 then
        print("number is odd")
elseif number == 42 then
        print("number is even")
elseif number == 43 then
        print("number is odd")
elseif number == 44 then
        print("number is even")
elseif number == 45 then
        print("number is odd")
elseif number == 46 then
        print("number is even")
elseif number == 47 then
        print("number is odd")
elseif number == 48 then
        print("number is even")
elseif number == 49 then
        print("number is odd")
elseif number == 50 then
        print("number is even")
elseif number == 51 then
        print("number is odd")
elseif number == 52 then
        print("number is even")
elseif number == 53 then
        print("number is odd")
elseif number == 54 then
        print("number is even")
elseif number == 55 then
        print("number is odd")
elseif number == 56 then
        print("number is even")
elseif number == 57 then
        print("number is odd")
elseif number == 58 then
        print("number is even")
elseif number == 59 then
        print("number is odd")
elseif number == 60 then
        print("number is even")
elseif number == 61 then
        print("number is odd")
elseif number == 62 then
        print("number is even")
elseif number == 63 then
        print("number is odd")
elseif number == 64 then
        print("number is even")
elseif number == 65 then
        print("number is odd")
elseif number == 66 then
        print("number is even")
elseif number == 67 then
        print("number is odd")
elseif number == 68 then
        print("number is even")
elseif number == 69 then
        print("number is odd")
elseif number == 70 then
        print("number is even")
elseif number == 71 then
        print("number is odd")
elseif number == 72 then
        print("number is even")
elseif number == 73 then
        print("number is odd")
elseif number == 74 then
        print("number is even")
elseif number == 75 then
        print("number is odd")
elseif number == 76 then
        print("number is even")
elseif number == 77 then
        print("number is odd")
elseif number == 78 then
        print("number is even")
elseif number == 79 then
        print("number is odd")
elseif number == 80 then
        print("number is even")
elseif number == 81 then
        print("number is odd")
elseif number == 82 then
        print("number is even")
elseif number == 83 then
        print("number is odd")
elseif number == 84 then
        print("number is even")
elseif number == 85 then
        print("number is odd")
elseif number == 86 then
        print("number is even")
elseif number == 87 then
        print("number is odd")
elseif number == 88 then
        print("number is even")
elseif number == 89 then
        print("number is odd")
elseif number == 90 then
        print("number is even")
elseif number == 91 then
        print("number is odd")
elseif number == 92 then
        print("number is even")
elseif number == 93 then
        print("number is odd")
elseif number == 94 then
        print("number is even")
elseif number == 95 then
        print("number is odd")
elseif number == 96 then
        print("number is even")
elseif number == 97 then
        print("number is odd")
elseif number == 98 then
        print("number is even")
elseif number == 99 then
        print("number is odd")
elseif number == 100 then
        print("number is even")
elseif number == 101 then
        print("number is odd")
elseif number == 102 then
        print("number is even")
elseif number == 103 then
        print("number is odd")
elseif number == 104 then
        print("number is even")
elseif number == 105 then
        print("number is odd")
elseif number == 106 then
        print("number is even")
elseif number == 107 then
        print("number is odd")
elseif number == 108 then
        print("number is even")
elseif number == 109 then
        print("number is odd")
elseif number == 110 then
        print("number is even")
elseif number == 111 then
        print("number is odd")
elseif number == 112 then
        print("number is even")
elseif number == 113 then
        print("number is odd")
elseif number == 114 then
        print("number is even")
elseif number == 115 then
        print("number is odd")
elseif number == 116 then
        print("number is even")
elseif number == 117 then
        print("number is odd")
elseif number == 118 then
        print("number is even")
elseif number == 119 then
        print("number is odd")
elseif number == 120 then
        print("number is even")
elseif number == 121 then
        print("number is odd")
elseif number == 122 then
        print("number is even")
elseif number == 123 then
        print("number is odd")
elseif number == 124 then
        print("number is even")
elseif number == 125 then
        print("number is odd")
elseif number == 126 then
        print("number is even")
elseif number == 127 then
        print("number is odd")
elseif number == 128 then
        print("number is even")
elseif number == 129 then
        print("number is odd")
elseif number == 130 then
        print("number is even")
elseif number == 131 then
        print("number is odd")
elseif number == 132 then
        print("number is even")
elseif number == 133 then
        print("number is odd")
elseif number == 134 then
        print("number is even")
elseif number == 135 then
        print("number is odd")
elseif number == 136 then
        print("number is even")
elseif number == 137 then
        print("number is odd")
elseif number == 138 then
        print("number is even")
elseif number == 139 then
        print("number is odd")
elseif number == 140 then
        print("number is even")
elseif number == 141 then
        print("number is odd")
elseif number == 142 then
        print("number is even")
elseif number == 143 then
        print("number is odd")
elseif number == 144 then
        print("number is even")
elseif number == 145 then
        print("number is odd")
elseif number == 146 then
        print("number is even")
elseif number == 147 then
        print("number is odd")
elseif number == 148 then
        print("number is even")
elseif number == 149 then
        print("number is odd")
elseif number == 150 then
        print("number is even")
elseif number == 151 then
        print("number is odd")
elseif number == 152 then
        print("number is even")
elseif number == 153 then
        print("number is odd")
elseif number == 154 then
        print("number is even")
elseif number == 155 then
        print("number is odd")
elseif number == 156 then
        print("number is even")
elseif number == 157 then
        print("number is odd")
elseif number == 158 then
        print("number is even")
elseif number == 159 then
        print("number is odd")
elseif number == 160 then
        print("number is even")
elseif number == 161 then
        print("number is odd")
elseif number == 162 then
        print("number is even")
elseif number == 163 then
        print("number is odd")
elseif number == 164 then
        print("number is even")
elseif number == 165 then
        print("number is odd")
elseif number == 166 then
        print("number is even")
elseif number == 167 then
        print("number is odd")
elseif number == 168 then
        print("number is even")
elseif number == 169 then
        print("number is odd")
elseif number == 170 then
        print("number is even")
elseif number == 171 then
        print("number is odd")
elseif number == 172 then
        print("number is even")
elseif number == 173 then
        print("number is odd")
elseif number == 174 then
        print("number is even")
elseif number == 175 then
        print("number is odd")
elseif number == 176 then
        print("number is even")
elseif number == 177 then
        print("number is odd")
elseif number == 178 then
        print("number is even")
elseif number == 179 then
        print("number is odd")
elseif number == 180 then
        print("number is even")
elseif number == 181 then
        print("number is odd")
elseif number == 182 then
        print("number is even")
elseif number == 183 then
        print("number is odd")
elseif number == 184 then
        print("number is even")
elseif number == 185 then
        print("number is odd")
elseif number == 186 then
        print("number is even")
elseif number == 187 then
        print("number is odd")
elseif number == 188 then
        print("number is even")
elseif number == 189 then
        print("number is odd")
elseif number == 190 then
        print("number is even")
elseif number == 191 then
        print("number is odd")
elseif number == 192 then
        print("number is even")
elseif number == 193 then
        print("number is odd")
elseif number == 194 then
        print("number is even")
elseif number == 195 then
        print("number is odd")
elseif number == 196 then
        print("number is even")
elseif number == 197 then
        print("number is odd")
elseif number == 198 then
        print("number is even")
elseif number == 199 then
        print("number is odd")
elseif number == 200 then
        print("number is even")

but that takes too long to type , so i occasionally use

local num = 10

if num%2 == 0 then
  print("it's even!")
else
  print("it's odd >:(")
5 Likes
#14

I think we already established that this isn’t a good idea.

#15

:rofl: :rofl: :rofl: :rofl:

30CHHHAAARRRSSSSSSSSSSSSSSSSSSSS

@DasKairo I’m pretty sure it was a joke.

1 Like
#16

I really like the first solution, I don’t know why people are trashing on my original solution as well, it does the same thing, but automates it… I thought it was pretty clever… The modulo might be too expensive to calculate :confused:

2 Likes
#17

I’m not trashing it, I’m just saying its a bit unnecessary

#18

@black1shadow1048, I’m sorry to copy your script here but, I’ve made some changes and it works:

local Number = 0

while task.wait(1) do
	Number=math.random(0,999)
	if Number%2 == 0 then
		print(Number..", it's even")
	else
		print(Number..", it's odd")
	end
end
2 Likes
#19

If it works, mark his script as solution

#20

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