105 lines
1.8 KiB
Markdown
105 lines
1.8 KiB
Markdown
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---
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id: 5d792533bb38fab70b27f527
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title: Step 16
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challengeType: 0
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dashedName: step-16
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---
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# --description--
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`arg1` and `arg2` are the numbers input by the user in a string such as "1+3".
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Pass `parseFloat(arg1)` and `parseFloat(arg2)` as the arguments to `infixToFunction[fn]` (remember `infixToFunction[fn]` is a function).
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# --hints--
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See description above for instructions.
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```js
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const regex = /([0-9.]+)([+-\/*])([0-9.]+)/;
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assert(
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infixEval('23+35', regex) === '58' &&
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infixEval('100-20', regex) === '80' &&
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infixEval('10*10', regex) === '100' &&
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infixEval('120/6', regex) === '20'
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);
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```
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# --seed--
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## --before-user-code--
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```html
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<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<title>Spreadsheet</title>
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<style>
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#container {
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display: grid;
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grid-template-columns: 50px repeat(10, 200px);
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grid-template-rows: repeat(11, 30px);
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}
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.label {
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background-color: lightgray;
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text-align: center;
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vertical-align: middle;
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line-height: 30px;
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}
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</style>
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</head>
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<body>
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<div id="container">
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<div></div>
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</div>
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```
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## --after-user-code--
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```html
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</body>
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</html>
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```
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## --seed-contents--
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```html
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<script>
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const infixToFunction = {
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"+": (x, y) => x + y,
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"-": (x, y) => x - y,
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"*": (x, y) => x * y,
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"/": (x, y) => x / y
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};
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--fcc-editable-region--
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const infixEval = (str, regex) =>
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str.replace(regex, (match, arg1, fn, arg2) =>
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infixToFunction[fn]
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);
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--fcc-editable-region--
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</script>
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```
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# --solutions--
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```html
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<script>
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const infixToFunction = {
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"+": (x, y) => x + y,
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"-": (x, y) => x - y,
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"*": (x, y) => x * y,
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"/": (x, y) => x / y
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};
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const infixEval = (str, regex) =>
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str.replace(regex, (match, arg1, fn, arg2) =>
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infixToFunction[fn](parseFloat(arg1), parseFloat(arg2))
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);
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</script>
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```
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