let YEAR = 1998;
function getCan(number){
  switch(number){
    case 0:{
      return "Canh"
    }
    case 1:{
      return "Tân"
    }
    case 2:{
      return "Nhâm"
    }
    case 3:{
      return "Quý"
    }
    case 4:{
      return "Giáp"
    }
    case 5:{
      return "Ất"
    }
    case 6:{
      return "Bính"
    }
    case 7:{
      return "Đinh"
    }
    case 8:{
      return "Mậu"
    }
    case 9:{
      return "Kỷ"
    }
    default:{
      return "Undefine";
    }
  }
}
function getChi(number){
  switch(number){
    case 0:{
      return "Thân"
    }
    case 1:{
      return "Dậu"
    }
    case 2:{
      return "Tuất"
    }
    case 3:{
      return "Hợi"
    }
    case 4:{
      return "Tý"
    }
    case 5:{
      return "Sửu"
    }
    case 6:{
      return "Dần"
    }
    case 7:{
      return "Mão"
    }
    case 8:{
      return "Thìn"
    }
    case 9:{
      return "Tỵ"
    }
    case 10:{
      return "Ngọ"
    }
    case 11:{
      return "Mùi"
    }
    default:{
      return "Undefine";
    }
  }
}
function getHanhCan(yearOld){ //1998 -> 8
  let strYear = yearOld.toString();
  let lastCharNum = strYear.substr(strYear.length-1,1);
  return parseInt(lastCharNum);
}
function getHanhChi(yearOld){ //1998 -> 8
  return yearOld % 12;
}
function getYearConvension(yearOld){
  return `${getCan(getHanhCan(yearOld))} ${getChi(getHanhChi(yearOld))}` ;
}
function getThienCan(canNum){
  if(canNum == 4 || canNum == 5){
    return 1;
  }
  if(canNum == 6 || canNum == 7){
    return 2;
  }
  if(canNum == 8 || canNum == 9){
    return 3;
  }
  if(canNum == 0 || canNum == 1){
    return 4;
  }
  if(canNum == 2 || canNum == 3){
    return 5;
  }
}
function getDiaChi(numChi){
  if(numChi == 4 || numChi == 5 || numChi == 10 || numChi == 11){
    return 0;
  }
  if(numChi == 0 || numChi == 1 || numChi == 6 || numChi == 7){
    return 1;
  }
    if(numChi == 2 || numChi == 3 || numChi == 8 || numChi == 9){
    return 2;
  }
}
function getNguHanh(num){
  switch(num){
    case 1:{
      return "Kim"
    }
    case 2:{
      return "Thủy"
    }
    case 3:{
      return "Hỏa"
    }
    case 4:{
      return "Thổ"
    }
    case 5:{
      return "Mộc"
    }
    default:{
      return "Undefine";
    }
  }
}
function getMenhNguHanh(yearOld){
  let can = getHanhCan(yearOld);
  let chi = getHanhChi(yearOld);
  let thienCan = getThienCan(can);
  let diaChi = getDiaChi(chi);
  let nguHanh = (thienCan + diaChi) > 5 ? (thienCan + diaChi) - 5 : (thienCan + diaChi);
  return getNguHanh(nguHanh)
}
console.log(`Năm: ${getYearConvension(YEAR)}`);
console.log(`Mệnh: ${getMenhNguHanh(YEAR)}`);