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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops Refactor Using a Loop

Posted by ammarkhan
.a{fill-rule:evenodd;}techdegree
ammarkhan
Front End Web Development Techdegree Student 21,661 Points

even number challenge

I am trying to do the challenge where (I think) we need to find % of 2. As I need to move the redundant code into loop, so I tired following

for(var i = 2; i % 0 ; i++){
    console.log(i)
}
var i = 2;
if(i % 2 === 0){

}

I think my logic is wrong as it is my first time doing it. I want to print even number upto 24

script.js 
console.log(2);
console.log(4);
console.log(6);
console.log(8);
console.log(10);
console.log(12);
console.log(14);
console.log(16);
console.log(18);
console.log(20);
console.log(22);
console.log(24);

for(var i = 2; i / 2 ; i++){
    console.log(i)
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

A "for" loop has 3 clauses: initialization, condition, and loop expression.

The initialization establishes the start: var i = 2 means the loop will start with the value 2 in "i".

The condition determines if it will repeat. Since you want it to go up to (and including) 24, a good condition might be: i <= 24

Then the loop expression is what should happen before the repeat. Since you want only even numbers, it would make sense to increase "i" by 2: i += 2

ammarkhan
.a{fill-rule:evenodd;}techdegree
ammarkhan
Front End Web Development Techdegree Student 21,661 Points

That was easy, why not i+2 why i+=2?

Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

The expression "i + 2" returns the correct value but doesn't store it anywhere. But "i += 2" stores the new value back into the variable "i".