ClickHouse/libs/libcommon/include/common/intExp.h

#pragma once

#include <cstdint>
#include <limits>


/// On overlow, the function returns unspecified value.

inline uint64_t intExp2(int x)
{
    return 1ULL << x;
}

inline uint64_t intExp10(int x)
{
    if (x < 0)
        return 0;
    if (x > 19)
        return std::numeric_limits<uint64_t>::max();

    static const uint64_t table[20] =
    {
        1ULL,                   10ULL,                   100ULL,
        1000ULL,                10000ULL,                100000ULL,
        1000000ULL,             10000000ULL,             100000000ULL,
        1000000000ULL,          10000000000ULL,          100000000000ULL,
        1000000000000ULL,       10000000000000ULL,       100000000000000ULL,
        1000000000000000ULL,    10000000000000000ULL,    100000000000000000ULL,
        1000000000000000000ULL, 10000000000000000000ULL
    };

    return table[x];
}

namespace common
{

inline int exp10_i32(int x)
{
    static const int values[] = {
        1,
        10,
        100,
        1000,
        10000,
        100000,
        1000000,
        10000000,
        100000000,
        1000000000
    };
    return values[x];
}

inline int64_t exp10_i64(int x)
{
    static const int64_t values[] = {
        1ll,
        10ll,
        100ll,
        1000ll,
        10000ll,
        100000ll,
        1000000ll,
        10000000ll,
        100000000ll,
        1000000000ll,
        10000000000ll,
        100000000000ll,
        1000000000000ll,
        10000000000000ll,
        100000000000000ll,
        1000000000000000ll,
        10000000000000000ll,
        100000000000000000ll,
        1000000000000000000ll
    };
    return values[x];
}

inline __int128 exp10_i128(int x)
{
    static const __int128 values[] = {
        static_cast<__int128>(1ll),
        static_cast<__int128>(10ll),
        static_cast<__int128>(100ll),
        static_cast<__int128>(1000ll),
        static_cast<__int128>(10000ll),
        static_cast<__int128>(100000ll),
        static_cast<__int128>(1000000ll),
        static_cast<__int128>(10000000ll),
        static_cast<__int128>(100000000ll),
        static_cast<__int128>(1000000000ll),
        static_cast<__int128>(10000000000ll),
        static_cast<__int128>(100000000000ll),
        static_cast<__int128>(1000000000000ll),
        static_cast<__int128>(10000000000000ll),
        static_cast<__int128>(100000000000000ll),
        static_cast<__int128>(1000000000000000ll),
        static_cast<__int128>(10000000000000000ll),
        static_cast<__int128>(100000000000000000ll),
        static_cast<__int128>(1000000000000000000ll),
        static_cast<__int128>(1000000000000000000ll) * 10ll,
        static_cast<__int128>(1000000000000000000ll) * 100ll,
        static_cast<__int128>(1000000000000000000ll) * 1000ll,
        static_cast<__int128>(1000000000000000000ll) * 10000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000ll,
        static_cast<__int128>(1000000000000000000ll) * 1000000ll,
        static_cast<__int128>(1000000000000000000ll) * 10000000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000ll,
        static_cast<__int128>(1000000000000000000ll) * 1000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 10000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 1000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 10000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 1000000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 10000000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000000000ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000000000ll * 10ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000000000ll * 100ll,
        static_cast<__int128>(1000000000000000000ll) * 100000000000000000ll * 1000ll
    };
    return values[x];
}

}