---
title: Sum All Numbers in a Range
---
 Remember to use **`Read-Search-Ask`** if you get stuck. Try to pair program  and write your own code 
###  Problem Explanation:
You need to create a program that will take an array of two numbers who are not necessarily in order, and then add not just those numbers but any numbers in between. For example, [3,1] will be the same as `1+2+3` and not just `3+1`
##  Hint: 1
Use `Math.max()` to find the maximum value of two numbers.
> _try to solve the problem now_
##  Hint: 2
Use `Math.min()` to find the minimum value of two numbers.
> _try to solve the problem now_
##  Hint: 3
Remember to that you must add all the numbers in between so this would require a way to get those numbers.
> _try to solve the problem now_
## Spoiler Alert!
**Solution ahead!**
##  Basic Code Solution:
function sumAll(arr) {
var max = Math.max(arr[0], arr[1]);
var min = Math.min(arr[0], arr[1]);
var temp = 0;
for (var i=min; i <= max; i++){
temp += i;
}
return(temp);
}
sumAll([1, 4]);
 Run Code
### Code Explanation:
* First create a variable to store the max number between two.
* The same as before for the Smallest number.
* We create a temporary variable to add the numbers.
Since the numbers might not be always in order, using `max()` and `min()` will help organize.
#### Relevant Links
* Math.max()
* Math.min()
* For Loops
##  Intermediate Code Solution:
const sumAll = (arr) => {
// Buckle up everything to one!
const startNum = arr[0];
const endNum = arr[1];
// Get the count of numbers between the two numbers by subtracting them and add 1 to the absolute value.
// ex. There are |1-4| + 1 = 4, (1, 2, 3, 4), 4 numbers between 1 and 4.
const numCount = Math.abs(startNum - endNum) + 1
// Using Arithmetic Progression summing formula
const sum = (startNum + endNum) * numCount / 2;
return sum;
};
 Run Code
### Code Explanation:
* The formula for calculating the sum of a continuous range is "(startNum + endNum) * numCount / 2".
* arr[0] and arr[1] can either be startNum or endNum, order doesn't matter.
* We can get the count of numbers in range by "Math.abs(arr[0] - arr[1]) + 1".
* Applying the formula by plugging in the numbers.
#### Relevant Links
* Array.sort()
* Arithmetic Progression summing formula
* ES6 arrow function
##  Advanced Code Solution:
function sumAll(arr) {
var sum = 0;
for (var i = Math.min(...arr); i <= Math.max(...arr); i++){
sum += i;
}
return sum;
}
sumAll([1, 4]);
 Run Code
### Code Explanation:
* Creating a variable sum to store the sum of the elements.
* Starting iteration of the loop from min element of given array and stopping when it reaches the max element.
* Using a spread operator (...arr) allows passing the actual array to the function instead of one-by-one elements.
#### Relevant Links
* Spread Operator
* Using Spread Operator in Math.max()
##  NOTES FOR CONTRIBUTIONS:
*  **DO NOT** add solutions that are similar to any existing solutions. If you think it is **_similar but better_**, then try to merge (or replace) the existing similar solution.
* Add an explanation of your solution.
* Categorize the solution in one of the following categories — **Basic**, **Intermediate** and **Advanced**. 