whats wrong in this ? im getting a[0-9]=0000?Any help will be appreciated : public class HexaDecimal {
	public String binary(String s)
	{
		String[] a= {"0000","0001","0010","0011","0100","0101","0110","0111","1000","1001","1010","1011","1100","1101","1110","1111"};
		
		
		String k="";
		for(int i=0;i<=s.length()-1;i++)
		{
			if(s.charAt(i)=='a'){k+=a[10];}
			else if(s.charAt(i)=='b'){	k+=a[11];}
			else if(s.charAt(i)=='c'){k+=a[12];}
			else if(s.charAt(i)=='d') {k+=a[13];}
			else if(s.charAt(i)=='e') {k+=a[14];}
			else if(s.charAt(i)=='f'){k+=a[15];}
			else{k+=a[i];}
			
		}
		return k;
		
	}

}

