xor

I recently started playing around with C#, and I'm trying to understand why the following code doesn't compile. On the line with the error comment, I get: Cannot implicitly convert type 'int' to 'char'. An explicit conversion exits (are you missing a cast?) I'm trying to do a simple XOR operation with two strings. public string calcXor (string a, string b) { char[] charAArray = a.ToCharArray(); char[] charBArray = b.ToCharArray(); char[] result = new char[6]; int len = 0; // Set length to be the length of the shorter string if (a.Length > b.Length) len = b.Length - 1; else len = a.Length - 1;

How can the XOR operation (on two 32 bit ints) be implemented using only basic arithmetic operations? Do you have to do it bitwise after dividing by each power of 2 in turn, or is there a shortcut? I don't care about execution speed so much as about the simplest, shortest code. Edit: This is not homework, but a riddle posed on a hacker.org . The point is to implement XOR on a stack-based virtual machine with very limited operations (similar to the brainfuck language and yes - no shift or mod). Using that VM is the difficult part, though of course made easier by an algorithm that is short and

Basically to make this quick and simple, I'm looking to run an XOR conditional in django template. Before you ask why don't I just do it in the code, this isn't an option. Basically I need to check if a user is in one of two many-to-many objects. req.accepted.all and req.declined.all Now they can only be in one or the other (hence the XOR conditional). From the looking around on the docs the only thing I can figure out is the following {% if user.username in req.accepted.all or req.declined.all %} The problem I'm having here is that if user.username does indeed appear in req.accepted.all then

How can I implement XOR using basic mathematical operators like +,-,*,/ Update: Actually, I need to track change in two matrix having Boolean values. This can be done using XORing each value with corresponding value in other matrix. But, Lp_Solve library doesn't support XOR operation. Also, it accepts only linear equations. (a − b)² This works because: (a − b)² = a * (a − b) + b * (b − a) Since multiplication in ℤ₂ is conjuction ( & ), and 1 - a is negation ( ! ), the above formula is equivalent to XOR for a, b ∈ {0, 1} : (a & !b) | (b & !a) See the comment below by Pascal Cuoq explaining why

This question already has an answer here: Easy interview question got harder: given numbers 1..100, find the missing number(s) given exactly k are missing 44 answers I have been given a list of n integers and these integers are in the range of 1 to n. There are no duplicates in list.But one of the integers is missing in the list.I have to find the missing integer. Example: If n=8 I/P [7,2,6,5,3,1,8] O/P 4 I am using a simple concept to find the missing number which is to get the sum of numbers total = n*(n+1)/2 And then Subtract all the numbers from sum. But the above method will fail if the

I have heard about people starting encryption and thought it may be something I would like, so I checked XOR and can't make any sense of it. So can someone explain to me what XOR is ? XOR is a logical operation, pronounced exclusive or . It can be used to cipher messages simply and fast. You can see a truth table for this operation here: http://mathworld.wolfram.com/XOR.html quasi-pseudo code implementation (via http://www.evanfosmark.com/2008/06/xor-encryption-with-python/) : #!/usr/bin/env python from itertools import izip, cycle def xor_crypt_string(data, key): return ''.join(chr(ord(x) ^

I need to check if two integers are on the same side of zero many times. I don't care if it's positive or negative, just that it's the same side... and performance is very important. Currently I'm doing this: if (int1 == 0 || int2 == 0) { // handle zero } else if ((int1 ^ int2) > 0) { // different side } else { // same side } This is a 30% improvement in speed (tested with caliper ) over the more obvious: if ((int1 > 0 && int2 > 0) || (int1 < 0 && int2 < 0)) { Can it be done faster? If anyone wants to see the test framework I'm using for the 30%, it's here. I used caliper 0.5-rc1 NOTE: All of

If we know the sum and XOR of two numbers, then can we find out what are the two numbers? I am trying to resolve a problem and the above problem is a part of that. Although, I do have another solution for that problem but I still want a solution for this. No. Example: SUM=7, XOR=7 Possible answers: a) 1, 6 b) 2, 5 c) 3, 4 Not enough information to decide which pair (a, b or c) is the original pair of numbers. 来源： https://stackoverflow.com/questions/25565626/determine-numbers-based-on-their-sum-and-xor