decode

/*
Ceasar Cipher

The Ceasar cipher is a basic encryption technique used by Julius Ceasar to securely communicate 
with his generals. Each letter is replaced by another letter N positions down the english alphabet. 
For example, for a rotation of 5, the letter 'c' would be replaced by an 'h'. 
In case of a 'z', the alphabet rotates and it is transformed into a ‘e’.
Implement a decoder for the Ceasar cipher where N = 5.

*/

    

public String decode(String code) {

	char[] c = code.toCharArray();

	for (int i=0; i<c.length; i++) {
    
		if (c[i]+5 > 'z') {
		
			c[i] = (char)(c[i]+5 - ('z'-'a'+1)); // alphabet length = 'z'-'a'+1
		}
		else c[i] = (char)(c[i]+5);		
	}
	
	return String.valueOf(c);
}