public class Solution {    public String multiply(String num1, String num2) {        int[] digits=new int[num1.length()+num2.length()];        for(int i=0;i
     
      =0;i--)        {            if(i>0)                digits[i-1]+=digits[i]/10;            sb.insert(0,(char)('0'+digits[i]%10));        }        int idx=0;        while(idx