JSFiddle - React, Tailwind, and code Playground
JavaScript
var reci = "BOoOOG otac", reg = /[A-Z]/;
for(var ii = 0; ii < reci.length-1; ++ii) {
document.write(reci.charAt(ii) + ": " + (reci.charAt(ii).test(reg) ? "<strong>C</strong>" : "L"));
document.write("<br/>");
}