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The bitwise XOR may be used to invert selected bits in a register (also called toggle or flip). Any bit may be toggled by XORing it with 1. For example, given the bit pattern 0010 (decimal 2) the second and fourth bits may be toggled by a bitwise XOR with a bit pattern containing 1 in the second and fourth positions:
A bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits.It is a fast, primitive action directly supported by the central processing unit (CPU), and is used to manipulate values for comparisons and calculations.
For example where denotes the exclusive disjunction (XOR) operation. [2] This operation is sometimes called modulus 2 addition (or subtraction, which is identical). [ 3 ] With this logic, a string of text can be encrypted by applying the bitwise XOR operator to every character using a given key.
In this example implementation for a bitwise trie with bitmap, nodes are placed in an array of long (64-bit) integers. A node is identified by the position (index) in that array. The index of the root node marks the root of the trie. Nodes are allocated from unused space in that array, extending the array if necessary.
In computer science, a mask or bitmask is data that is used for bitwise operations, particularly in a bit field.Using a mask, multiple bits in a byte, nibble, word, etc. can be set either on or off, or inverted from on to off (or vice versa) in a single bitwise operation.
Trie data structures are commonly used in predictive text or autocomplete dictionaries, and approximate matching algorithms. [11] Tries enable faster searches, occupy less space, especially when the set contains large number of short strings, thus used in spell checking, hyphenation applications and longest prefix match algorithms.
Bitboards allow the computer to answer some questions about game state with one bitwise operation. For example, if a chess program wants to know if the white player has any pawns in the center of the board (center four squares) it can just compare a bitboard for the player's pawns with one for the center of the board using a bitwise AND operation.
Both ciphers are built on a pseudorandom function based on add–rotate–XOR (ARX) operations — 32-bit addition, bitwise addition (XOR) and rotation operations. The core function maps a 256-bit key, a 64-bit nonce, and a 64-bit counter to a 512-bit block of the key stream (a Salsa version with a 128-bit key also exists). This gives Salsa20 ...