DEV Community

Ticha Godwill Nji
Ticha Godwill Nji

Posted on • Updated on

How to add two numbers in JavaScript without using the "+" operator?

We can add two numbers in Javascript without using the + operator. Let me show you how to do this computation using JS functions.

Let's start by declaring a function name add and pass in 2 parameters (a,b) to the function

const add = (a,b)=>{

}
Enter fullscreen mode Exit fullscreen mode

After declaring the function, let's now add the logic in the function block that will do the computation.

const add = (a,b)=>{
for(i = 1; i <= b; i++ ){
a++
}
return a
}
Enter fullscreen mode Exit fullscreen mode

We initiates a for loop. The loop starts with i equal to 1 and continues as long as i is less than or equal to b. i is incremented by 1 in each iteration.

a++
Enter fullscreen mode Exit fullscreen mode

Inside the loop, a is being incremented by 1 in each iteration. This effectively adds 1 to a, b times.

return a;

Enter fullscreen mode Exit fullscreen mode

After the loop finishes, the value of a is returned. This will be the original value of a plus b.

console.log(add(3, 5)); //output: 8

Enter fullscreen mode Exit fullscreen mode

Click here to watch the video on Youtube

Top comments (10)

Collapse
 
seanhurwitz profile image
seanhurwitz
function add(x,y) {
return Array(x).fill("").concat(Array(y).fill("")).length
}
Enter fullscreen mode Exit fullscreen mode
Collapse
 
ticha profile image
Ticha Godwill Nji

Great solution! However, it might not work well for large and negative numbers

Collapse
 
kiliaosi profile image
wangzhi
function add(x, y) {
    while (y != 0) {
        let carry = x & y;
        x = x ^ y;
        y = carry << 1;
    }
    return x;
}
Enter fullscreen mode Exit fullscreen mode
Collapse
 
ticha profile image
Ticha Godwill Nji

Great solution! I think you should consider how it will handle floating point numbers!

Collapse
 
citronbrick profile image
CitronBrick

Here's mine:

    function add(a,b) {
        return a - (b * -1);
    }
Enter fullscreen mode Exit fullscreen mode

Thanking my 8th grade teachers for this :)

Collapse
 
slobodan4nista profile image
Slobi • Edited
function add(a,b) {
        return -(-a-b);
    }
Enter fullscreen mode Exit fullscreen mode
Collapse
 
ticha profile image
Ticha Godwill Nji

Hey there! Your function for addition is clever and brings back some nostalgic memories with your shoutout to your 8th-grade teachers. I appreciate the humor and personal touch in the comment!

Collapse
 
jonrandy profile image
Jon Randy 🎖️
let a = 5
a += 2
Enter fullscreen mode Exit fullscreen mode

No + operator here! :)

Collapse
 
ticha profile image
Ticha Godwill Nji

:)

Collapse
 
citronbrick profile image
CitronBrick

You can enable syntax highlighting in dev using

triple backtick javascript
code
triple backtick