export function swapCase(text: string): string {
  let res: string = ''
  for (let i: number = 0; i < text.length; i++) {
    const currLetter: string = text[i];
    if (currLetter.toLowerCase() === currLetter) res += currLetter.toUpperCase();
    else res += currLetter.toLowerCase();
  }
  return res;
}