RosettaCodeData/Task/Non-continuous-subsequences/C++/non-continuous-subsequences...

16 lines
402 B
C++

/*
* Nigel Galloway, July 19th., 2017 - Yes well is this any better?
*/
class N{
uint n,i,g,e,l;
public:
N(uint n): n(n-1),i{},g{},e(1),l(n-1){}
bool hasNext(){
g=(1<<n)+e;for(i=l;i<n;++i) g+=1<<i;
if (l==2) {l=--n; e=1; return true;}
if (e<((1<<(l-1))-1)) {++e; return true;}
e=1; --l; return (l>0);
}
uint next() {return g;}
};