js面试题用for循环输出三角形

Question

    *

   **

  ***

 ****

*****

提示：找任意一行，空格，星星的个数与行号的规律！
请问用for循环，console.log输出怎么写？

Answer 1

var&nbsp;str='&nbsp;&nbsp;&nbsp;&nbsp;*****' for(var&nbsp;i=0;i<5;i++){&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;var&nbsp;str1=str.slice(i,i+5) &nbsp;&nbsp;console.log(str1) }

Answer 2

我也来凑个热闹，打印任意行数的星星。function printStar(col) {&nbsp; &nbsp; for (var i=0; i<col; i++) {&nbsp; &nbsp; &nbsp; &nbsp; var spaceArr = new Array(col - i),&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; starArr = new Array(i + 2),&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; space = spaceArr.join(' '),&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; star = starArr.join('*');&nbsp; &nbsp; &nbsp; &nbsp; console.log(space + star);&nbsp; &nbsp; }}printStar(5);