console.log("Hello, World!");


function rot13(str) {
  str=str.split("")
let x="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
for(let i=0;i<str.length;i++){
  let y=x.indexOf(str[i])
  //console.log(y)
  if(y>=0 && y<13){
    //console.log(x[y+13])
    str[i]=x[y+13]
  }
  else if(y>=13){
    str[i]=x[13-(26-y)]
  }
}
  return str.join("");
}

console.log(rot13("SERR PBQR PNZC"))
console.log(rot13("ABCD EFGD"))