reverse the position of integer digits?

Question

i have to reverse the position of integer like this

input = 12345

output = 54321

i made this but it gives wrong output e.g 5432

#include         


        

Answer 1

template <typename T>
T reverse(T n, size_t nBits = sizeof(T) * 8)
{
    T reverse = 0;
    auto mask = 1;

    for (auto i = 0; i < nBits; ++i)
    {
        if (n & mask)
        {
            reverse |= (1 << (nBits - i - 1));
        }
        mask <<= 1;
    }

    return reverse;
}

This will reverse bits in any signed or unsigned integer (short, byte, int, long ...). You can provide additional parameter nBits to frame the bits while reversing.

i. e. 7 in 8 bit = 00000111 -> 11100000 7 in 4 bit = 0111 -> 1110