21 lines
428 B
C
21 lines
428 B
C
#include <assert.h>
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#include <limits.h>
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/*
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* Generate mask indicating rightmost 1 in x.
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* For example 0xFF00 -> 0x0100, and 0x6600 --> 0x0200.
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* If x == 0, then return 0.
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*/
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int rightmost_one(unsigned x) {
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return x & -x;
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}
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int main() {
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for (unsigned x = 0; ; x++) {
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assert((x == 0 && rightmost_one(x) == 0) || (x != 0 && rightmost_one(x) == (1 << __builtin_ctz(x))));
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if (x == UINT_MAX) {
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break;
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}
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}
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} |