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@arkku
Last active August 29, 2015 14:25
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ROR puzzle
uint32_t ror(const uint32_t w, const unsigned rot) { // ROtate Right (bits move `rot` places right w/ wraparound)
return (w >> rot) | (w << (32 - rot));
}
uint32_t a; // = ?
uint32_t rotation = 13;
uint32_t b = 0x29d34b82;
// b == a ^ ror(a, rotation)
// What is `a` when `b` was formed by `a ^ ror(a, rotation)`? There is more than one correct answer.
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arkku commented Jul 17, 2015

^ is the bitwise XOR operator, the function ror rotates bits to the right.

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