freeCodeCamp/curriculum/challenges/en/02-javascript-algorithms-and-data-structures/basic-javascript/compound-assignment-with-augmented-addition.en.md

id, title, challengeType

id	title	challengeType
56533eb9ac21ba0edf2244af	Compound Assignment With Augmented Addition	1

Description

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: myVar = myVar + 5; 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. One such operator is the += operator.

var myVar = 1;
myVar += 5;
console.log(myVar); // Returns 6

Instructions

Convert the assignments for a, b, and c to use the += operator.

Tests

- text: <code>a</code> should equal <code>15</code>
  testString: 'assert(a === 15, ''<code>a</code> should equal <code>15</code>'');'
- text: <code>b</code> should equal <code>26</code>
  testString: 'assert(b === 26, ''<code>b</code> should equal <code>26</code>'');'
- text: <code>c</code> should equal <code>19</code>
  testString: 'assert(c === 19, ''<code>c</code> should equal <code>19</code>'');'
- text: You should use the <code>+=</code> operator for each variable
  testString: 'assert(code.match(/\+=/g).length === 3, ''You should use the <code>+=</code> operator for each variable'');'
- text: Do not modify the code above the line
  testString: 'assert(/var a = 3;/.test(code) && /var b = 17;/.test(code) && /var c = 12;/.test(code), ''Do not modify the code above the line'');'

Challenge Seed

var a = 3;
var b = 17;
var c = 12;

// Only modify code below this line

a = a + 12;
b = 9 + b;
c = c + 7;

After Test

console.info('after the test');

Solution

var a = 3;
var b = 17;
var c = 12;

a += 12;
b += 9;
c += 7;