The phrase "adding two numbers" is correct and usable in written English.
You can use it in mathematical contexts or when discussing arithmetic operations.
Example: "The process of adding two numbers is fundamental in basic mathematics, such as when calculating the total cost of items."
Alternatives: "summing two numbers" or "calculating the total of two numbers".
Typical "operations" include comparing two numbers or adding two numbers together.
One problem deals with what I mentioned in the last section; if you are used to programming in Basic, you may think of displaying a text string as being of the same level of complexity as adding two numbers, while in reality adding two numbers is many times simpler and faster.
Such snippets encode handfuls of the most basic operations that computers perform: loading a number into memory, for instance, and then adding two numbers together.
The cell count, area and delay of two input adders such as Brent-Kung, Ladner-Ficher, Han-Carlson and Kogg-Stone are at least doubles when three numbers are added, compared to adding two numbers.
When the microprocessor receives an instruction to perform some task, such as adding two numbers together, that big instruction calls into play a sequence of tinier, more specific instructions that interact with the circuitry to carry out the addition.
Displaying a line of text in memory may not take much more code from you than adding two numbers in registers, but you should always remember that displaying the text involves running a function written by someone else, and that it involves a huge number of the basic operations.
(I confess I have caught myself adding three numbers in Excel). Computers were once used only for the most complex and important tasks, and the hurdle for getting access to one was high.
Working memory is the brain function that lets you carry on a phone conversation while adding three numbers in your head and remembering that you need to steer the car onto the freeway exit in about two minutes — all this time not forgetting who you're talking to.
One might thus write "add pay, total" instead of "0110101100101000" for an instruction that adds two numbers.
In an assembly-language instruction, instead of writing out a string of binary digits that might tell the machine to add two numbers one can simply write "ADD" in the program, and this will be translated into machine language.
