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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops Create a for Loop

Ryan Moye
Ryan Moye
4,107 Points
Posted by Ryan Moye
Ryan Moye
4,107 Points

I can't figure out how to set up this for loop

I wrote the code and I think it's mostly right, but I can't tell.

script.js 
var i = 0;
for ( i = 4; i <= 156; i += ) {
  console.log(i);
}

2 Answers

Antonio De Rose
Antonio De Rose
20,884 Points
Antonio De Rose
Antonio De Rose
20,884 Points 
var i = 0;
for ( i = 4; i <= 156; i += ) {
  console.log(i);
}

//you have already setted up the loop nicely, except for the incrementer which needs to added by 1
//and it would be a better practice to declare it within the brace, rather than declaring outside


//var i = 0; // this is redundant
for ( var i = 4; i <= 156; i += 1) {
  console.log(i);
}


// var i = 4 ->entering in the loop
//i <= 156 -> checks for the condition, if it is true, then go to the statement
//i+=1 -> increment it

//and finally, when i is 157, at that time, it will check condition, like below
//i <= 157
//it will exit from the { } block
Alexander Solberg
Alexander Solberg
14,350 Points
Alexander Solberg
Alexander Solberg
14,350 Points

You are declaring the "i" variable outside of the loop, which is what we typically do with a "while" loop, not in a "for" loop though. In a "for" loop, you declare the variable(most commonly "i") within the condition of the loop.

Also, "i +=" is indicating that "i" is supposed to be added with some value, however, you aren't passing any value. It should be something like(ignore quotes) "i += 1", or better yet, "i++"(if you simply increment by +1).

The following code will pass the challenge. 

for (var i = 4; i <= 156; i++) {
  console.log(i);
}