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#ifndef ZIG_ZAG_INL_H_
#error "Direct inclusion of this file is not allowed, include zig_zag.h"
// For the sake of sane code completion.
#include "zig_zag.h"
#endif
#undef ZIG_ZAG_INL_H_
namespace NYT {
////////////////////////////////////////////////////////////////////////////////
inline ui32 ZigZagEncode32(i32 n)
{
// Note: the right-shift must be arithmetic.
// Note: left shift must be unsigned because of overflow.
return (static_cast<ui32>(n) << 1) ^ static_cast<ui32>(n >> 31);
}
inline i32 ZigZagDecode32(ui32 n)
{
// Note: using unsigned types prevent undefined behavior.
return static_cast<i32>((n >> 1) ^ (~(n & 1) + 1));
}
inline ui64 ZigZagEncode64(i64 n)
{
// Note: the right-shift must be arithmetic.
// Note: left shift must be unsigned because of overflow.
return (static_cast<ui64>(n) << 1) ^ static_cast<ui64>(n >> 63);
}
inline i64 ZigZagDecode64(ui64 n)
{
// Note: using unsigned types prevent undefined behavior.
return static_cast<i64>((n >> 1) ^ (~(n & 1) + 1));
}
////////////////////////////////////////////////////////////////////////////////
} // namespace NYT
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