why this code is giving unexpected res. ?

Question

actually i could not understand how char functions
https://code.sololearn.com/ccyWVMJojN9F/?ref=app

Answer 1

tqq sir

Answer 2

Every char has an associated ascii number, the ascii number for 'z' is 122. When you add res and a together java automatically casts the char into its ascii number.
If you want the char you have to cast the number into a char like (char)res2.
Also you can cast doubles like 122.9 into a char, it will just chop off the decimal and return the ascii 122.

Here's a table of all asciis
https://www.cs.cmu.edu/~pattis/15-1XX/common/handouts/ascii.html

Answer 3

How are you working with double and int at the end you add the value of the 'a' character with res so you will get a number. What you have to do is convert to get the character
System.out.println((char)res2);

Answer 4

tqq sir