How to Add two optional variables

[daring roost]

I had written Zig program. which is get values from user and add those two values and display them but problem is how to add two optional variables

[rapid ginkgo]

if you are certain they have a value you can use either variable.? or, more secure, variable orelse your_preferred_way_to_handle_the_error

you can also use the if (optional_variable) |variable| pattern but it will get a bit more verbose

I am not sure I grasped the meaning of your question, if I don't don't hesitate to ask again

[daring roost]

I am new to zig and I didn't know how to get user input like C function scanf or gets is there any way to get user inputs like C?

[shell copper]

Getting user input is an OS thing, so yes you can.
In Zig's case, I would suggest something like this:

const stdin_handle = std.io.getStdIn();
const stdin = stdin_handle.reader();

const line = (try stdin.readUntilDelimiterOrEofAlloc(allocator, '\n', 4096).?;
defer allocator.free(line);

The 4096 is the maximum number of bytes to read before giving up - which is useful if the amount of data being read is very large, for instance.
But for a line of user input, a relatively small value is probably more useful, depending on exactly what you're doing.

[rapid ginkgo]

yeah, it's a little more convoluted in Zig because you have to be very specific. In scanf you get a ton of implicit stuff

[shell copper]

Right.

There also readUntilDelimiterOrEof which takes a buffer to write into instead of allocating, if that's more to your liking, as well, incidentally.

[daring roost]

While compiling this code i got error

test2.zig:5:78: error: expected ')', found ';'
const line = (try stdin.readUntilDelimiterOrEofAlloc(allocator, '\n', 4096).?;

[shell copper]

Oh, I missed a paren 🤣

Should be 4096))

[daring roost]

Allocator also does not declared

[shell copper]

Sure - you need to an allocator from somewhere.
You can make one like this for your purposes:

var gpa = std.heap.GeneralPurposeAllocator(.{}) {};
const allocator = gpa.allocator();

You can put this in main, and then pass this allocator around to anything that needs it.