# Sum All Numbers in a Range Help

Sum All Numbers in a Range Help
0

#1

Tell us what’s happening:
My code is passing the first three tests but not the last two… which is weird because by the logic it should? Any help appreciated

Your code so far

``````function sumAll(arr) {
var big = Math.max(arr[0], arr[1]);
return (big*(big+1)/2);
}

sumAll([1, 4]);
``````

Your browser information:

Your Browser User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36`.

Link to the challenge:

#2

Looking back at this I am seeing that it returns 55 for [5, 10]. Obviously, my algorithm is because it is starting at 1 instead of arr[0].

#3

function sumAll(arr) {
var big = Math.max(arr[0], arr[1]);
var small = (Math.min(arr[0], arr[1]) -1);
return (big*(big+1)/2) - (small*(small+1)/2);
}

Fixed it

#4

My idea…

function sumAll(arr){
let a= arr[0];
let b= arr[1];
return ((Math.abs(a-b))+1)*(a+b)/2;
}
var kq= sumAll([10,4]);
console.log(kq);