102 lines
1.6 KiB
Markdown
102 lines
1.6 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244af
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title: Compound Assignment With Augmented Addition
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cDR6LCb'
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forumTopicId: 16661
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dashedName: compound-assignment-with-augmented-addition
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---
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# --description--
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In programming, it is common to use assignments to modify the contents of a variable. Remember that everything to the right of the equals sign is evaluated first, so we can say:
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```js
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myVar = myVar + 5;
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```
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to add `5` to `myVar`. Since this is such a common pattern, there are operators which do both a mathematical operation and assignment in one step.
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One such operator is the `+=` operator.
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```js
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var myVar = 1;
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myVar += 5;
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console.log(myVar);
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```
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`6` would be displayed in the console.
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# --instructions--
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Convert the assignments for `a`, `b`, and `c` to use the `+=` operator.
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# --hints--
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`a` should equal `15`.
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```js
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assert(a === 15);
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```
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`b` should equal `26`.
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```js
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assert(b === 26);
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```
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`c` should equal `19`.
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```js
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assert(c === 19);
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```
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You should use the `+=` operator for each variable.
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```js
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assert(code.match(/\+=/g).length === 3);
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```
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You should not modify the code above the specified comment.
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```js
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assert(
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/var a = 3;/.test(code) &&
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/var b = 17;/.test(code) &&
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/var c = 12;/.test(code)
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);
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```
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# --seed--
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## --after-user-code--
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```js
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(function(a,b,c){ return "a = " + a + ", b = " + b + ", c = " + c; })(a,b,c);
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```
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## --seed-contents--
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```js
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var a = 3;
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var b = 17;
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var c = 12;
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// Only change code below this line
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a = a + 12;
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b = 9 + b;
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c = c + 7;
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```
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# --solutions--
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```js
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var a = 3;
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var b = 17;
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var c = 12;
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a += 12;
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b += 9;
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c += 7;
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```
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