Learn: Bitwise tricks
Operators: & (and), | (or), ^ (xor), ~ (not), << and >> (shift).
```csharp
int n = 12; // 1100 in binary
Console.WriteLine(n & 1);
Console.WriteLine((n & (n - 1)) == 0);
Console.WriteLine(5 ^ 3 ^ 5);
Console.WriteLine(1 << 4);
```
n & 1 is 0 for even numbers. n > 0 && (n & (n - 1)) == 0 is true only for powers of two (.NET also has int.IsPow2). x ^ x is 0, so xor finds the one number without a pair. 1 << 4 is 16.
Use them for flags, compact sets of booleans, and these classic interview tricks.
Read more: https://www.geeksforgeeks.org/dsa/bitwise-algorithms/
#tip · TIP-042
codementor
npub1u6…v0yg2
2026-10-27 16:07:58 UTC
Author Public Key
npub1u69qs4hfpkve0v0hy85s2fycjeqjm4ts8xdfs7ew3l270l87yfuspv0yg2Seen on
wss://relay.primal.netPublished at
2026-10-27 16:07:58 UTCEvent JSON
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"content": "Learn: Bitwise tricks\n\nOperators: \u0026 (and), | (or), ^ (xor), ~ (not), \u003c\u003c and \u003e\u003e (shift).\n\n```csharp\nint n = 12; // 1100 in binary\nConsole.WriteLine(n \u0026 1);\nConsole.WriteLine((n \u0026 (n - 1)) == 0);\nConsole.WriteLine(5 ^ 3 ^ 5);\nConsole.WriteLine(1 \u003c\u003c 4);\n```\n\nn \u0026 1 is 0 for even numbers. n \u003e 0 \u0026\u0026 (n \u0026 (n - 1)) == 0 is true only for powers of two (.NET also has int.IsPow2). x ^ x is 0, so xor finds the one number without a pair. 1 \u003c\u003c 4 is 16.\nUse them for flags, compact sets of booleans, and these classic interview tricks.\n\nRead more: https://www.geeksforgeeks.org/dsa/bitwise-algorithms/\n\n#tip · TIP-042",
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