I have a school project question (for Python) that goes like this:
Given a string_input such as "abcd&1-4efg", the function must remove the "&1-4" and insert the string slice from 1 to 4 where the "&1-4" was.
eg. if string_input = "abcd&1-4efg",
"&1-4" is removed.
The remaining characters are indexed as follows: a=0, b=1, c=2, d=3, e=4, f=5, g=6
The new string becomes: "abcdbcdeefg"
I've managed to write a long chunk of code to do this, but I'm wondering if anyone has any more efficient solutions?
Things to note:
- The instructions can include double digits (eg. &10-15)
- If the index isn't found, the returned string should print "?" for every missing index (eg. "abcd&5-10efgh" would return "abcdfgh???efgh")
- Intructions can be back-to-back (eg. "&10-15abcdef&1-5&4-5pqrs")
The code I've written is:
def expand(text):
text += "|"
import string
digits_dash = string.digits + "-"
idx_ref_str = ""
replace_list = []
record_val = False
output_to_list = []
instruct = ""
and_idx_mark = 0
#builds replace_list & idx_ref_list
for idx in range(len(text)):
if text[idx] == "&" and record_val==True:
output_to_list.append(instruct)
output_to_list.append(and_idx_mark)
replace_list.append(output_to_list)
output_to_list, instruct, inst_idx, and_idx_mark = [],"",0,0
and_idx_mark = idx
continue
elif text[idx] == "&":
record_val = True
and_idx_mark = idx
continue
#executes if currently in instruction part
if record_val == True:
#adds to instruct
if text[idx] in digits_dash:
instruct += text[idx]
#take info, add to replace list
else:
output_to_list.append(instruct)
output_to_list.append(and_idx_mark)
replace_list.append(output_to_list)
output_to_list, instruct, inst_idx, and_idx_mark, record_val = [],"",0,0,False
#executes otherwise
if record_val == False:
idx_ref_str += text[idx]
idx_ref_str = idx_ref_str[:-1]
text = text[:-1]
#converts str to int indexes in replace list[x][2]
for item in replace_list:
start_idx = ""
end_idx = ""
#find start idx
for char in item[0]:
if char in string.digits:
start_idx += char
elif char == "-":
start_idx = int(start_idx)
break
#find end idx
for char in item[0][::-1]:
if char in string.digits:
end_idx = char + end_idx
elif char == "-":
end_idx = int(end_idx)
break
start_end_list = [start_idx,end_idx]
item+=start_end_list
#split text into parts in list
count = 0
text_block = ""
text_block_list = []
idx_replace = 0
for char in text:
if char == "&":
text_block_list.append(text_block)
text_block = ""
count += len(replace_list[idx_replace][0])
idx_replace +=1
elif count > 0:
count -= 1
else:
text_block += char
text_block_list.append(text_block)
#creates output str
output_str = ""
for idx in range(len(text_block_list)-1):
output_str += text_block_list[idx]
#creates to_add var to add to output_str
start_repl = replace_list[idx][1]
end_repl = replace_list[idx][1] + len(replace_list[idx][0])
find_start = replace_list[idx][2]
find_end = replace_list[idx][3]
if end_idx >= len(idx_ref_str):
gap = end_idx + 1 - len(idx_ref_str)
to_add = idx_ref_str[find_start:] + "?" * gap
else:
to_add = idx_ref_str[find_start:find_end+1]
output_str += to_add
output_str += text_block_list[-1]
return output_str
import string
in the middle of a function? \$\endgroup\$