1.4 replace

public class replacechar 
{
	public static void main(String[] args) {
		String s = "Mr John Smith";
		String ms = add(s);

		System.out.println(s);
		System.out.println(ms);
	}

	public static String add(String s)
	{
		// count num of ''
		int count = 0;
		for(int i = 0; i < s.length(); i++)
		{
			if(s.charAt(i) == ' ')
				count++;
		}

		char[] result = new char[s.length() + count*2];
		int j = 0;
		for(int i = 0; i < s.length(); i++)
		{
			if(s.charAt(i) == ' ')
			{
				result[j] = '%';
				result[j+1] = '2';
				result[j+2] = '0';
				j += 2;
			}
			else
				result[j] = s.charAt(i);
			j++;
		}

		String sresult = new String(result);
		return sresult;
	}
}

Hi, I think there is an error in line 30. It should be j +=3 instead of j+=2.

The spaces at the end of the String should be ignored!
What's more, if implements in Java, the input type should be char[] rather than string. Because the Question required perform this operation in place