Function rot13

7.GraphQL Apocalypse/server/crypto/flagEncoder.ts:1–7

(str: string)

function rot13(str: string): string {
  return str.replace(/[a-zA-Z]/g, (char) => {
    const code = char.charCodeAt(0);
    const base = code >= 97 ? 97 : 65;
    return String.fromCharCode(((code - base + 13) % 26) + base);
  });
}

function rot13Reverse(str: string): string {
  return rot13(str);