# Learn Functional Programming by Building a Spreadsheet - Step 25

### Tell us what’s happening:

The first element of the array passed to the average() function should be the element at the middle + 1 index of the sorted array

``````<!-- file: index.html -->
<!DOCTYPE html>
<html lang="en">
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<body>
<div id="container">
<div></div>
</div>
<script src="./script.js"></script>
</body>
</html>
``````
``````/* file: styles.css */
#container {
display: grid;
grid-template-columns: 50px repeat(10, 200px);
grid-template-rows: repeat(11, 30px);
}

.label {
background-color: lightgray;
text-align: center;
vertical-align: middle;
line-height: 30px;
}
``````
``````/* file: script.js */
const isEven = num => num % 2 === 0;
const sum = nums => nums.reduce((acc, el) => acc + el, 0);
const average = nums => sum(nums) / nums.length;

// User Editable Region

const median = nums => {
const sorted = nums.slice().sort((a, b) => a - b);
const length = sorted.length;
const middle = length / 2 - 1;
return isEven(length)
? average([sorted(length / 2 - 1) + 1, sorted(length / 2)])
: sorted[Math.ceil(length / 2)];
};

// User Editable Region

const range = (start, end) => Array(end - start + 1).fill(start).map((element, index) => element + index);
const charRange = (start, end) => range(start.charCodeAt(0), end.charCodeAt(0)).map(code => String.fromCharCode(code));

const container = document.getElementById("container");
const createLabel = (name) => {
const label = document.createElement("div");
label.className = "label";
label.textContent = name;
container.appendChild(label);
}
const letters = charRange("A", "J");
letters.forEach(createLabel);
range(1, 99).forEach(number => {
createLabel(number);
letters.forEach(letter => {
const input = document.createElement("input");
input.type = "text";
input.id = letter + number;
input.ariaLabel = letter + number;
container.appendChild(input);
})
})
}
``````

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36 Edg/124.0.0.0`

### Challenge Information:

Learn Functional Programming by Building a Spreadsheet - Step 25

• wrong expressions
• make use of “sorted”, “middle”, “middle+1” in ternary expressions

happy coding

thank you…it worked like a charm

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