--- id: 6449755666005520330cec5b title: Step 29 challengeType: 0 dashedName: step-29 --- # --description-- Since your `update` event is running as a `change` event listener, the `event` parameter will be a change event. The `target` property of the change event represents the element that changed. Assign the `target` property to a new variable called `element`. # --hints-- You should declare an `element` variable in your `update` function. ```js assert.match(code, /const\s+update\s*=\s*(\(\s*event\s*\)|event)\s*=>\s*\{\s*(?:var|let|const)\s+element/); ``` You should use `const` to declare your `element` variable. ```js assert.match(code, /const\s+update\s*=\s*(\(?\s*event\s*\)|event)\s*=>\s*\{\s*const\s+element/); ``` You should assign the `target` property of the `event` parameter to your `element` variable. ```js assert.match(code, /const\s+update\s*=\s*(\(\s*event\s*\)|event)\s*=>\s*\{\s*const\s+element\s*=\s*event\.target/); ``` # --seed-- ## --seed-contents-- ```html Functional Programming Spreadsheet
``` ```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; } ``` ```js const isEven = num => num % 2 === 0; const sum = nums => nums.reduce((acc, el) => acc + el, 0); const average = nums => sum(nums) / nums.length; 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[middle], sorted[middle + 1]]) : sorted[Math.ceil(middle)]; } const spreadsheetFunctions = { sum, average, median } 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)); window.onload = () => { 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; input.onchange = update; container.appendChild(input); }) }) } --fcc-editable-region-- const update = event => { } --fcc-editable-region-- ```