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ASCII code decode to string

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;

0

$begingroup$

Hi i am working on this question and have my answer as following. I guess the time complexity is Big O(n ^2), anyone know the better solution for Big O(n)?

A string is encoded by performing the following sequence of actions:
1. Replace each character with its ASCII value representation.
2. Reverse the string.

For example, the table below shows the conversion from the string "HelloWorld" to the ASCII string
"7210110810811187111114108100":

Character
H e l l o W o r l d
ASCII Value
72 101 108 108 111 87 111 114 108 100

The ASCII string is then reversed to get the encoded string "0018014111117811180180110127".

The characters in encoded string are within the range 10 - 126 which include special characters.

 def asciiencode(s: str) -> str:
 s = s[::-1]
 ch_map = str(i): chr(i) for i in range(10, 127)
 res = []

 def decode(s, substr):
 if not s: return res.append(substr)
 for i in (2, 3):
 if s[:i] in ch_map:
 decode(s[i:], substr + ch_map[s[:i]])

 decode(s, '')
 return res

python python-3.x

share

asked 3 mins ago

A.LeeA.Lee

637

$endgroup$

add a comment | 

0

$begingroup$

Hi i am working on this question and have my answer as following. I guess the time complexity is Big O(n ^2), anyone know the better solution for Big O(n)?

A string is encoded by performing the following sequence of actions:
1. Replace each character with its ASCII value representation.
2. Reverse the string.

For example, the table below shows the conversion from the string "HelloWorld" to the ASCII string
"7210110810811187111114108100":

Character
H e l l o W o r l d
ASCII Value
72 101 108 108 111 87 111 114 108 100

The ASCII string is then reversed to get the encoded string "0018014111117811180180110127".

The characters in encoded string are within the range 10 - 126 which include special characters.

 def asciiencode(s: str) -> str:
 s = s[::-1]
 ch_map = str(i): chr(i) for i in range(10, 127)
 res = []

 def decode(s, substr):
 if not s: return res.append(substr)
 for i in (2, 3):
 if s[:i] in ch_map:
 decode(s[i:], substr + ch_map[s[:i]])

 decode(s, '')
 return res

python python-3.x

share

asked 3 mins ago

A.LeeA.Lee

637

$endgroup$

add a comment | 

$begingroup$

Hi i am working on this question and have my answer as following. I guess the time complexity is Big O(n ^2), anyone know the better solution for Big O(n)?

A string is encoded by performing the following sequence of actions:
1. Replace each character with its ASCII value representation.
2. Reverse the string.

For example, the table below shows the conversion from the string "HelloWorld" to the ASCII string
"7210110810811187111114108100":

Character
H e l l o W o r l d
ASCII Value
72 101 108 108 111 87 111 114 108 100

The ASCII string is then reversed to get the encoded string "0018014111117811180180110127".

The characters in encoded string are within the range 10 - 126 which include special characters.

 def asciiencode(s: str) -> str:
 s = s[::-1]
 ch_map = str(i): chr(i) for i in range(10, 127)
 res = []

 def decode(s, substr):
 if not s: return res.append(substr)
 for i in (2, 3):
 if s[:i] in ch_map:
 decode(s[i:], substr + ch_map[s[:i]])

 decode(s, '')
 return res

python python-3.x

share

asked 3 mins ago

A.LeeA.Lee

637

$endgroup$

 def asciiencode(s: str) -> str:
 s = s[::-1]
 ch_map = str(i): chr(i) for i in range(10, 127)
 res = []

 def decode(s, substr):
 if not s: return res.append(substr)
 for i in (2, 3):
 if s[:i] in ch_map:
 decode(s[i:], substr + ch_map[s[:i]])

 decode(s, '')
 return res

share

asked 3 mins ago

A.LeeA.Lee

637

share

asked 3 mins ago

A.LeeA.Lee

637

asked 3 mins ago

A.LeeA.Lee

637

asked 3 mins ago

A.LeeA.Lee

637