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JavaScript

Posted by Jennifer Hughes
Jennifer Hughes
11,421 Points

For loop nested within a for loop

Hello!

I am trying to understand how the following code words; can anyone please explain it to me keeping in mind that I am a beginner? Thanks!!

x=[-1,-2,3,-4,-5];

for(var j = 0; j<x.length; j++){
  for(var i=0; i<x.length-1; i++){
    if(x[i]<0){
      var temp = x[i];
      x[i] = x[i+1];
      x[i+1] = temp;
    }
  }
}

for(var g=x.length-1; g>=0; g--){
  if(x[x.length-1] <0){
  x.pop();
  }
}

console.log(x);

2 Answers

shezazr
shezazr
8,275 Points
shezazr
shezazr
8,275 Points

have added comments to each line.. 

for(var j = 0; j<x.length; j++){   // this is the outer loop.. it will loop 5 times
  for(var i=0; i<x.length-1; i++){  // for each of the outer loop.. this will run 4 times.. so in total 4*5
    if(x[i]<0){  // this is checking if current value i.e. x[0] which is -1 is less than 0 
      var temp = x[i];  // create a temporary variable
      x[i] = x[i+1];  // make the temp var = the NEXT element in the x in this case it will be -2
      x[i+1] = temp;  // set the value of next element equal to the temp variable
    }
  }
}
Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi shez azr,

You had the 3 backticks correct but there needs to be a blank line before your opening 3 backticks. I went ahead and fixed your code formatting for you.

Joel Smith
Joel Smith
14,779 Points
Joel Smith
Joel Smith
14,779 Points

shez azr:

Here's a tip that I just learned from one of the instructors when adding code to a comment or an answer;

Wrap it with this

' ' '[syntax type] [code here] ' ' '

Use the offhand quote that is just under the ~ symbol on your keyboard. Also, [syntax type] is html or javascript or php. whatever the code type is.

This will help your answers be more coherent. Good answer though. :)

Joel Smith
Joel Smith
14,779 Points

don't include the brackets [], though.