let x = 0&&123;
console.log(x)

let u = ""||123;
console.log(u)

if(""){
  console.log(1)
}

var a = 0;
if(true){
  a=1;
  function a(){}// let a = function(){}
  a=21;
  console.log('a1:',a)
}
console.log('a2:',a)