Substring outofindex

Question

I wrote a code for which

if 23E+20 is the input then output should be 230000000(20 zeros)

if 4.456E-14 is the input then 4.456000(14 zeros) should be the output

But its not working properly. Please let me know where I did error. Thank You.

using System;

class test

{

public static void Main()

{

Console.WriteLine("Enter double");

      String ext =Console.ReadLine();



           if(ext.IndexOf("E")!=-1)
        {
           int i=ext.IndexOf("E");

          ext = ext.Substring(0, i);

          for (int j = 0; j < int.Parse(ext.Substring(i + 1, ext.Length - (i + 1))); j++)

          ext = ext + "0";         

          Console.WriteLine(ext);



      }

}   

Console.ReadKey();
}
}

Answer 1

You are probably going out of bounds of the string, remember always use i-1 index for last letter of array of size i(assuming arrays that start at 0 which is what most languages use). Although it just an educated guess as I don't know C#.

Answer 2

This might be a simpler solution to your problem:

String s = Console.ReadLine();
Double d = Double.Parse(s);
Console.WriteLine(d.ToString("0.#############################################################################"));

Answer 3

When you substring ext in ext = ext.Substring(0,i) you are assigning ext = "4.456" and cutting away the e-part

when you do ext.Length - (i + 1) in the for loop you get a negative index

Try this instead

int noZeroes = Int32.Parse(ext.Substring(i + 1))
ext = ext.Substring(0, i);
string zeroString = new string('0', noZeroes)

ext += zeroString;