let ast = ''
let size = 8

for(let i=1; i<=size; i++) {
  if(i % 2 == 0) {
    ast += ' '
  }
    for(let j=1; j<=size; j++) {
      if(j % 2 == 0) {
        ast += '#'
      } else {
        ast += ' '
      }
    }
  ast += '\n'
  console.log(ast)
  ast = ''
}