My solution not working!

#1

else{
for(int i=0; i<=r; i++){
if(last == i)even = true;
if(second_last == i) odd = true;
ans += go(pos+1, tight & (i == r) , start | (i>0), even , odd , i, last);
}
}

#2

Please go through the tutorial video of the video.
Maybe there’s some error in other part of solution.
Sharing just this snippet wont’t help