def find_max_substr(astring):
max_sub_str, temp = [], []
left_ptr, right_ptr = 0, 0
total = len(astring)
while right_ptr < total:
cur_str = astring[right_ptr]
if cur_str not in temp:
temp.append(cur_str)
right_ptr += 1
else:
if len(temp) > len(max_sub_str):
max_sub_str = temp
index = temp.index(cur_str)
left_ptr = left_ptr+index+1
temp = [astring[j] for j in range(left_ptr, right_ptr)]
if len(temp) > len(max_sub_str):
max_sub_str = temp
return max_sub_str
astring = 'asdfabcefghijk'
ret = find_max_substr(astring)
print(''.join(ret), len(ret))