I dont know why am i fails. this is so ridiculous

Question about the task

Bit operations

Java Multithreading, Level 10, Lesson 6

Under discussion

I use only allowed operators but still fail on exactly this condition

You must implement a public int resetLowerBits(int number) method. It should clear all the bits in the number argument, except the highest bit set to one, and then return this number.
An int is 4 bytes = 32 bits. If the number 3456 is passed to the method, its bit representation would be 00000000 00000000 00001101 10000000. The method needs to clear all the lower bits, i.e. the bit representation of the expected return value is: 00000000 00000000 00001000 00000000.
This number is 2048.

Some more examples:
Example 1:
Input: 1
Output: 1

Example 2:
Input: 4
Output: 4

Example 3:
Input: 255
Output: 128

The resetLowerBits method parameter can be from 1 to Integer.MAX_VALUE, inclusive.
Use only the following operations:
1) =
2) |
3) &
4) >>
5) <<
6) ~
7) digits from 0 to 9 inclusive
8) Curly braces
9) a return statement to send back the return value.

You CAN'T create variables, use loops, conditional statements, and so on.
Don't change the name of the resetLowerBits method's parameter (it must be "number").
The main method is not tested.

Requirements:

The class Solution should have a public int resetLowerBits(int) method.
The resetLowerBits(int) method's parameter should be called number.
In the Solution class's resetLowerBits(int) method, use only the allowed operations.
The resetLowerBits method should work according to the task conditions.

package com.codegym.task.task30.task3013; /* Bit operations */ public class Solution { public static void main(String[] args) { Solution solution = new Solution(); int number = Integer.MAX_VALUE - 133; System.out.println(Integer.toString(number, 2)); String result = Integer.toString(solution.resetLowerBits(number), 2); System.out.println(result); } public int resetLowerBits(int number) { //write your code here number |= number>>1; number |= number>>2; number |= number>>4; number |= number>>8; number |= number>>8>>8; number &= number>>1; //number = number<<1; return number+1; } }

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Wei Cui

Level 39 , Newark, United States

17 April 2020, 18:43

public int resetLowerBits(int number) {
        //write your code here
        number &= ~(number >> 1);
        number &= ~(number >> 2);
        number &= ~(number >> 4);
        number &= ~(number >> 8);
        number &= ~(number >> 16);
        return number;
    }

Tony Roy

Level 41 , Victorville, United States

11 May 2020, 13:50

I am puzzled by this response. It validates. But it seems transparently not to give the right results (try number = 13, or just the hard-coded value in the problem). A solution that verifies *and* gives the right results is like "nobody" above but starting at 25, number |= (number >> 16); number &= (~number) >> 1; return number;

Justin Smith

Level 41 , Greenfield, USA, United States

23 July 2022, 20:48

I think he may have used number>>8>>8 because one of the condition rules says "digits from 0 to 9 inclusive". But since the official solution uses the number 16, I'm interpreting that rule to simply mean that the numbers must be made up of normal base-10 digits (meaning you can't use something like hexadecimal, not that you would have any reason to).