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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Using For Loops with Arrays

Aakash Srivastav
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Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 Points
Posted by Aakash Srivastav
.a{fill-rule:evenodd;}techdegree
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 Points

reversing array with for loop

Why doesn't initializing n within the for loop reverse the order of array elements. My code is-

var lotOfNames = ["Aakash" , "Shubham" , "Ankit" , "Shanu"];
function reverseArray( newArray ){

    for( let i = 0 ; i < Math.floor(n/2) ; i++){
                var n = newArray.length;
        let temp = newArray[i];
        newArray[i] = newArray[n-i-1];
        newArray[n-i-1] = temp;
    }
    return newArray;
}
console.log(reverseArray(lotOfNames));

When I run this code . It prints the same array. But when I initialised n outside for loop , function works and it print the reverse order of elements as expected. I know its silly to do such thing. But i was just experimenting with the code.

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The loop depends on the value of "n" in the condition clause ("i < Math.floor(n / 2)"). So if "n" is not established before the loop starts, then the condition is false to start with and the loop does not run.