[JavaScript] - js拼接字符串

原题

var countSheep = function (num){
  //your code here
  var str = ' sheep...';
  var result = '';
  for (var i=1;i<num+1;++i){
    result+=(i+str);
  }
  return result;
}

CW解:

countSheep=n=>[...Array(n).keys()].map(x=>`${x+1} sheep...`).join``

var countSheep = function (n){
  return [...Array(n)].map((_,i)=>i+1+' sheep...').join``
}

const countSheep = num => {
  let val = '';
  for (let i = 1; i <= num; i++) {
    val += `${i} sheep...`;
  }
  return val;
}