In this shot, we’ll discuss three ways to sum up all the numbers in a given range in JavaScript.
Our program should accept an array of two numbers as input, for example, sumAll([1, 3])
. Then, it should process the sum of all the numbers in the given range. It should be noted that both the numbers in the given range are inclusive, that is, 1
and 3
in this example. Finally, the program should return the total/sum as output, which is 6
in the case of this example.
The lowest number will not always come first. Hence, [3,1]
should be treated as [1,3]
.
for
loopfunction sumAll(arr) {if (arr[0] > arr[1]) // if the highest number is on the left, sort the arrayarr.sort((a, b) => a - b)let sum = 0 // Initialize a variable that will be holding the sumfor (let i = arr[0]; i <= arr[1]; i++) // Loop over the rangesum += ireturn sum // return result}console.log(sumAll([3,1]))
.reduce()
methodHere we will implement:
[1, 4]
=> [1, 2, 3, 4]
.reduce()
method.function sumAll(arr) {if (arr[0] > arr[1])arr.sort((a, b) => a - b)const newArr = []for(let i = arr[0]; i <= arr[1]; i += 1)newArr.push(i)return newArr.reduce((acc, cur) => acc + cur)}console.log(sumAll([3,1]))
We can also use methods other than reduce()
to get the sum of the newly created array items.
Happy coding!