String reverse(String s1){
		char c[]=new char[s1.length()];
		c=s1.toCharArray();
		
		for(int i=0;i<(s1.length()/2);i++){
			char temp=c[(s1.length()-1)-i];
			c[(s1.length()-1)-i]=c[i];
			c[i]=temp;
		}
		
		return new String(c);
	}