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f=lambda a,b,n=1,d=2:a>b and f(a-b,b,n*2+1,d*2)or a<b and f(a,b-a,n*2-1,d*2)or(n,d) Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
Improvement given by Bubbler's golf tipsBubbler. Original solution here.
f=lambda a,b,n=1,d=2:a>b and f(a-b,b,n*2+1,d*2)or a<b and f(a,b-a,n*2-1,d*2)or(n,d) Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
Improvement given by Bubbler's golf tips. Original solution here.
f=lambda a,b,n=1,d=2:a>b and f(a-b,b,n*2+1,d*2)or a<b and f(a,b-a,n*2-1,d*2)or(n,d) Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
Improvement given by Bubbler. Original solution here.
deff=lambda f(a,b,n=1,d=2): a>b whileand f(a!=b-b,b,n*2+1,d*2): or n*=2;d*=2 a<b and iff(a>b):a,n=a-b,n+1 else:b,n=b-a,nn*2-1 return ,d*2)or(n,d) Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
Improvement given by Bubbler's golf tips. Original solution here.
def f(a,b,n=1,d=2): while(a!=b): n*=2;d*=2 if(a>b):a,n=a-b,n+1 else:b,n=b-a,n-1 return n,d Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
f=lambda a,b,n=1,d=2:a>b and f(a-b,b,n*2+1,d*2)or a<b and f(a,b-a,n*2-1,d*2)or(n,d) Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.
Improvement given by Bubbler's golf tips. Original solution here.
def f(a,b,n=1,d=2): while(a!=b): n*=2;d*=2 if(a>b):a,n=a-b,n+1 else:b,n=b-a,n-1 return n,d Explanation: The sequence of turns starting from 1 down to the given fraction in the Stern-Brocot tree is identical to the sequence of turns starting from the given fraction going to 1 in the Calkin-Wilf tree. This makes it much simpler to get the sequence.