Explain the output please

Question

char[]chr = ("197").toCharArray();
int x1=Integer.parseInt(""+chr[1]);
System.out.println(""+x1+chr[1]);

Why 99 and not 18 as output? (ofc x1 and chr[1] is getting added)

Answer 1

"" + x1 + chr[1]

Here the + operator acts as string concatenation operator rather than arithmetic add operator. This is because you have an empty string before <x1>. When a + operator is placed between a string and a number the number is automatically converted to string, then the two will be concatenated.

"" + x1 + chr[1]

An empty string is concatenated with '9' => "9"

"9" + chr[1]

Here chr[1] will concatenated into the string to the left ("9"). Then we have a final result as "99".

Answer 2

<x1> is an int, while <chr[1]> is a char (an element of a char array).

Answer 3

You're welcome,
But is your doubt clear now? it's more important to understand. I'm not leaving you yet until it's all clear.

Answer 4

Ipang so, typeof x1 and chr[1], both are string or number ?

Answer 5

Ipang got it, thanks

Answer 6

Ipang this is what i got;
Equivalent to javascript, it is
console.log(""+9+"9");
so the output is 99
where 9 is for x1 and "9" is for chr[1]
Correct?

Answer 7

Noise Of Silence
That's absolutely right! you got it correctly 👍