Collatz

Source file	Python version	Characters with line endings	Characters without line endings	Comments
collatz.py	3.8	103	98	Range [1, 100000]
collatz2.py	3.8	108	107	Range [1, 100000]
collatz-python2.py	2.7	102	97	Range [1, 100000]
collatz2-python2.py	2.7	107	106	Range [1, 100000]
collatz3-python2.py	2.7	99	94	Range [1, 100000]
collatz4-python2.py	2.7	97	🔝🙌 92 🙌🔝	Range [0, 100000]

If collatz4-python2.py program is written in the Python Command Line, the print command can be avoided, writting only _. Obtaining 86 characters without line endings:

a=_=0
for n in range(100001):
	c,N=1,n
	while n>1:n=(n/2,n*3+1)[n%2];c+=1
	if c>a:a,_=c,N
_

Update With the [a-zA-Z0-9]* character count. There are 41 characters for PCL (python 2.7):

a=s=0
for _ in range(10**5+1):
	c,N=1,_
	while _>1:_=(_/2,_*3+1)[_%2];c+=1
	if c>a:a,s=c,N
s

29 characters with PCL and range [1, 100000] (python 2.7):

a=s=(""!="")
for _ in range((""==""),(((""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""==""))**((""=="")+(""=="")+(""=="")+(""=="")+(""==""))+(""==""))):
	c,N=(""==""),_
	while _>(""==""):_=(_/((""=="")+(""=="")),_*((""=="")+(""=="")+(""==""))+(""==""))[_%((""=="")+(""==""))];c+=(""=="")
	if c>a:a,s=c,N
s

17 characters with PCL and range [1, 100000] (python 2.7):

__=___=(""!="")
for _ in range((""==""),(((""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""==""))**((""=="")+(""=="")+(""=="")+(""=="")+(""==""))+(""==""))):
	____,_____=(""==""),_
	while _>(""==""):_=(_/((""=="")+(""=="")),_*((""=="")+(""=="")+(""==""))+(""==""))[_%((""=="")+(""==""))];____+=(""=="")
	if ____>__:__,___=____,_____
___

15 characters with PCL and range [1, 100000] (python 2.7):

__=___=(""!="")
for _ in range((""==""),(((""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""=="")+(""==""))**((""=="")+(""=="")+(""=="")+(""=="")+(""==""))+(""==""))):
	____,_____=(""==""),_
	while _>(""==""):_=(_/((""=="")+(""=="")),_*((""=="")+(""=="")+(""==""))+(""==""))[_%((""=="")+(""==""))];____+=(""=="")
	__,___=((__,___),(____,_____))[____>__]
___

10 characters writing collatz_underscore_pcl_4.py in PCL and range [1, 100000] (python 3.8). Only words for, in and while, added ~- and -~ operations to avoid n!=1 and c+=1, changed //2 to >>1:

_=''=='';__=_+_;___=__+_;____=___+_;_____=____+_;______=_____+_;_______=______+_;________=_______+_;_________=________+_;__________=_________+_;______________=~-_
___________ = [ ...avoided, check full file... ]

____________=_____________=______________
for ______________ in ___________:
	_______________,________________=_,______________
	while ~-______________:______________=(______________>>_,______________*___+_)[______________%__];_______________=-~_______________
	____________,_____________=((____________,_____________),(_______________,________________))[_______________>____________]
_____________

Better minimum implementation, 15 characters, print and two times while:

_=__=()!=[];____=_____=~-_
while __<(((-~-~_+-~_)*-~_)**(-~-~_+-~_)+_):
	___,______=_,__
	while ~-__:(__,___)=((__>>_,-~___),(__*-~-~_+_,-~___))[__%-~_]
	____,_____,__=((____,_____,-~______),(___,______,-~______))[___>____]
print(_____)

Just the calculation, 10 characters, two times while:

_=__=()!=[];____=_____=~-_
while __<(((-~-~_+-~_)*-~_)**(-~-~_+-~_)+_):
	___,______=_,__
	while ~-__:(__,___)=((__>>_,-~___),(__*-~-~_+_,-~___))[__%-~_]
	____,_____,__=((____,_____,-~______),(___,______,-~______))[___>____]

Just the calculation in Chinese Python, 0 characters, while is 當:

_=__=()!=[];____=_____=~-_
當 __<(((-~-~_+-~_)*-~_)**(-~-~_+-~_)+_):
	___,______=_,__
	當 ~-__:(__,___)=((__>>_,-~___),(__*-~-~_+_,-~___))[__%-~_]
	____,_____,__=((____,_____,-~______),(___,______,-~______))[___>____]

The same but with Chinese print 印出, 0 characters:

_=__=()!=[];____=_____=~-_
當 __<(((-~-~_+-~_)*-~_)**(-~-~_+-~_)+_):
	___,______=_,__
	當 ~-__:(__,___)=((__>>_,-~___),(__*-~-~_+_,-~___))[__%-~_]
	____,_____,__=((____,_____,-~______),(___,______,-~______))[___>____]
印出 _____

An alternative use of tupple unpacking with list addition:

_=__=()!=[];____=_____=~-_
while __<(((-~-~_+-~_)*-~_)**(-~-~_+-~_)+_):
	___,______=_,__
	while ~-__:__,___=[(__>>_,__*-~-~_+_)[__%-~_]]+[-~___]
	____,_____,__=([____,_____],[___,______])[___>____]+[-~______]
print(_____)

Only one while version. Readable version

_=n=c=N=()!=[];b=s=~-_
while N<=(((-~-~_+-~_)*-~_)**(-~-~_+-~_)):n,N,c,b,s=[-~_*[-~N]+[_]+[[b,s],[c,N]][c>b],[[n>>_],[n*-~-~_+_]][n%-~_]+[N,-~c,b,s]][n>_]
print(s)

Only one while version. 5 characters

_=__=___=_____=()!=[];______=_______=~-_
while _____<=(((-~-~_+-~_)*-~_)**(-~-~_+-~_)):__,_____,___,______,_______=[-~_*[-~_____]+[_]+[[______,_______],[___,_____]][___>______],[[__>>_],[__*-~-~_+_]][__%-~_]+[_____,-~___,______,_______]][__>_]

Chinese version. 0 characters

_=__=___=_____=()!=[];______=_______=~-_
當 _____<=(((-~-~_+-~_)*-~_)**(-~-~_+-~_)):__,_____,___,______,_______=[-~_*[-~_____]+[_]+[[______,_______],[___,_____]][___>______],[[__>>_],[__*-~-~_+_]][__%-~_]+[_____,-~___,______,_______]][__>_]
印出 _______

Chinese version, only calc. 0 characters

_=__=___=_____=()!=[];______=_______=~-_
當 _____<=(((-~-~_+-~_)*-~_)**(-~-~_+-~_)):__,_____,___,______,_______=[-~_*[-~_____]+[_]+[[______,_______],[___,_____]][___>______],[[__>>_],[__*-~-~_+_]][__%-~_]+[_____,-~___,______,_______]][__>_]

Extra version using a list and all numbers are made on-the-fly

_=[()!=[]]*-~-~-~(()!=[])+[()==[]]*-~([]!=())
while _[-~-~(()!=[])]<=((-~-~(()!=[])+-~(()!=[]))*-~(()!=[]))**(-~-~(()!=[])+-~(()!=[])):_[()!=[]],_[-~-~(()!=[])],_[-~(()!=[])],_[-~-~-~(()!=[])],_[-~-~-~-~(()!=[])]=[-~(()!=[])*[-~_[-~-~(()!=[])]]+[()!=[]]+[[_[-~-~-~(()!=[])],_[-~-~-~-~(()!=[])]],[_[-~(()!=[])],_[-~-~(()!=[])]]][_[-~(()!=[])]>_[-~-~-~(()!=[])]],[[_[()!=[]]>>(()!=[])],[_[()!=[]]*-~-~(()!=[])+(()!=[])]][_[()!=[]]%-~(()!=[])]+[_[-~-~(()!=[])],-~_[-~(()!=[])],_[-~-~-~(()!=[])],_[-~-~-~-~(()!=[])]]][_[()!=[]]>(()!=[])]
print(_[-~-~-~-~(()!=[])])

svilaa/Collatz

Collatz