What will be the output of the program?
Understand the Problem
The question is asking what the output of a given Java program will be, which involves understanding how the byte type works and how post-incrementing a byte value affects its output.
Answer
$129$
Answer for screen readers
The output of the program is $129$.
Steps to Solve
-
Initial Variable Assignment The code initializes a byte variable
x
with the value 127. Thus: $$ x = 127 $$ -
Post-Increment Operation The first increment operation
x++
increasesx
by 1. However, sincex
is a byte and starts at its maximum of 127, the increment will overflow: $$ x = 127 + 1 = 128 $$ -
Second Increment Operation The second increment operation
x++
increases the value ofx
from 128 to 129 without overflow: $$ x = 128 + 1 = 129 $$ -
Output Result The program will print the final value of
x
, which is now: $$ x = 129 $$
The output of the program is $129$.
More Information
In Java, the byte data type can hold values from -128 to 127. When exceeding this range, it wraps around. In this case, the increments stay within the byte range without causing an overflow after the first increment.
Tips
- Ignoring Overflow Behavior: Some may forget that byte types wrap around at their max/min values. This can lead to incorrect assumptions about the output.
- Misunderstanding Post-Increment: Confusing the effects of pre-increment and post-increment can lead to errors in predicting the final value.