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#pragma once
#include <stdint.h>
inline static uint32_t bit_length(uint32_t n) {
const uint32_t n_minus_1 = n - 1;
if (n_minus_1 == 0) {
return 0;
} else {
#ifdef _MSC_VER
unsigned long bsr;
_BitScanReverse(&bsr, n_minus_1);
return bsr + 1;
#else
return 32 - __builtin_clz(n_minus_1);
#endif
}
}
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