JSFiddle - React, Tailwind, and code Playground

HTML

<div id="result"></div>

JavaScript

function find_invalid_numbers(arr) {
    var nonvalid, i, max;
    
    nonvalid = [];
    
    if (arr.length !== 0) {
        max = arr[0];
        
        for (i = 1; i < arr.length; ++i) {
            if (arr[i] < max) {
                nonvalid.push(arr[i]);
            } else {
                max = arr[i];
            }
        }
    }
    
    return nonvalid;
}

var input = [1, 2, 3, 10, 5, 11, 12, 2, 4, 25];

$("#result").text(JSON.stringify(find_invalid_numbers(input)));