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#include <bit>

// 0x00 0x01 0x02 0x03
// 0    0    0    1         big endians
// 1    0    0    0         little endians

bool little_endians() {
    static union {
        int a;
        char b;
    } u{.a = 1};
    return u.b;
}

bool little_endians2() {
    static int i = 1;
    return *(char *)&i == 1;
}

bool little_endians3() { return std::endian::native == std::endian::little; }