binTodecSteroids

#include <iostream>

int main()
{
    int bin{ 0 };
    int dec{ 0 };
    std::cin >> bin;

    for (int mul{ 1 }, bit{ 0 }; (bit=bin%10), bin and ( (bit == 1 or bit == 0) ? 1 : dec = 0); (dec += ( bit * mul) ), mul *= 2, bin /= 10);

    std::cout << "Decimal number: " << dec << '\n';
}