JSFiddle - React, Tailwind, and code Playground

JavaScript

function checkPasswordComplexity(pwd) {
    var regularExpression = /^[a-zA-Z0-9]+$/;
    var valid = regularExpression.test(pwd);
    console.log(pwd,valid)
    return valid;
}

var passwords = ["a1","aaa1","a234qarfss34wsgfdQWew3e5rtdgf","  123    ","12qedsed54sdrgdfgdfgdfg","!##sa"];

var res = passwords.map(function(can){
    return can +" is a "+(checkPasswordComplexity(can)?"valid":"invalid") + " password";
}).join("<br />");

document.body.innerHTML = res;