Code Golf: Collatz Conjecture

Answer 1

The program frm Jerry Coffin has integer over flow, try this one:

#include 

int main(unsigned long long i)
{
    int j = 0;
    for(  std::cin>>i; i>1; i = i&1? i*3+1:i/2, ++j)
        std::cout< ";

    std::cout<<"\n"<

tested with

The number less than 100 million with the longest total stopping time is 63,728,127, with 949 steps.

The number less than 1 billion with the longest total stopping time is 670,617,279, with 986 steps.