Array comparison

[Lpsd]

Let's say I have two arrays

a = { "apple", "pear", "orange", "pineapple", "tomato" }
b = { "kiwi", "strawberry", "melon" }

How can I compare the two arrays, and detect the entries in array b which aren't in array a?

Edited December 10, 2016 by LopSided_

[MR.S3D]

Quote

i dont understand what you need.

 

[pa3ck]

I don't think there's a native LUA or MTA function for that, but something like this should work

local a = { "apple", "pear", "orange", "pineapple", "tomato" }
local b = { "kiwi", "strawberry", "melon", "apple", "tomato" }

function checkDuplicate(arr1, arr2)
	local duplicateEntries = {}
	for i = 1, #arr1 do
        local found = false
		for k = 1, #arr2 do
			if arr1[i] == arr2[k] then
				found = true
			end
		end
        if not found then
            table.insert(duplicateEntries, arr1[i])
        end
	end
	return duplicateEntries
end
    
local doubleEntries = checkDuplicate( a, b )
    
local strEntries = table.concat(doubleEntries, ",")
   
print(strEntries)

 

[Lpsd]

1 hour ago, pa3ck said:

I don't think there's a native LUA or MTA function for that, but something like this should work

local a = { "apple", "pear", "orange", "pineapple", "tomato" }
local b = { "kiwi", "strawberry", "melon", "apple", "tomato" }

function checkDuplicate(arr1, arr2)
	local duplicateEntries = {}
	for i = 1, #arr1 do
        local found = false
		for k = 1, #arr2 do
			if arr1[i] == arr2[k] then
				found = true
			end
		end
        if not found then
            table.insert(duplicateEntries, arr1[i])
        end
	end
	return duplicateEntries
end
    
local doubleEntries = checkDuplicate( a, b )
    
local strEntries = table.concat(doubleEntries, ",")
   
print(strEntries)

 

Works great as expected, thanks a bunch 

[pa3ck]

No problem.

[LoPollo]

I know the code pa3ck it's working, but once the element is found on the second array it's useless continue the loop, except if you want to count the number of elements in arr2 equals to an element in arr1, but the function is not made and still will not work in this case. So isn't it better to insert a "break" between line 11 and 12?

Have a nice day