Find array max in Javascript

Question

Is this code correct to find the max from an array? There are other ways to find the max, however the requirements are to use "for" loop!Thanks! Full reqs : "Create an array with 10 numbers of your choice and a variable named max. Assign 0 to max. In a for loop, find the greatest number, assign it to max and write it in the console."

var numArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var max = 0;
var arrLen = numArray.length;
for (i = 0; i < arrLen; i++) {
 if (numArray[i] - numArray[arrLen - 1] >= 0) {
 max = numArray[i];
 } else {
 continue;
 }
 console.log(max);
} 

• palaѕн: You can simply use: Math.max(...numArray)
• T.J. Crowder: @palaѕн - "...the requirements are to use "for" loop...".
• palaѕн: ok, then maybe this solution
• Junius L: I think this's a homework

Answer 1

Approach it like this:

1. Start with max at -Infinity.
2. Inside the loop body, if numArray[i] is greater than max, set max to numArray[i].
3. Show the result after the loop, since while the loop is still running, max may not be the maximum value yet.

At the end of the loop, max will contain the highest value in the array (or -Infinity if the array is empty).

---

Don't forget to declare all of your variables, including i.

• Alex Cocan: Thnanks TJ, however requirements are: max= 0; & use a "for" loop. See below: "Create an array with 10 numbers of your choice and a variable named max. Assign 0 to max. In a for loop, find the greatest number, assign it to max and write it in the console." I know about max/ and function to sort the array, however I need to follow reqs. Thoughts? Thanks!
• T.J. Crowder: @AlexCocan - The suggestion above is following those requirements. (Other than if the requirements really require you to display max from within the loop, but I think that's a misreading as it makes no sense to do that...)
• Alex Cocan: Thanks TJ, I used @ninascholz's solution, that works fine for me.

Answer 2

You could start with the first element as max value and iterate from index one.

Then check and change max if a new maximum is found.

Do not forget to declare all variables (like i).

var numArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
 max = numArray[0],
 arrLen = numArray.length,
 i;
for (i = 1; i < arrLen; i++) {
 if (numArray[i] > max) max = numArray[i];
}
console.log(max);

For having all numbers greater than zero, you could omit the assignment with first value and start index from zero.

var numArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
 max = 0,
 arrLen = numArray.length,
 i;
for (i = 0; i < arrLen; i++) {
 if (numArray[i] > max) max = numArray[i];
}
console.log(max);

• Alex Cocan: Thanks Nina, that works, however reqs are : max = 0; & use "for" loop. Thoughts? Thanks!