he-010
1.000
Challenge · difficulty 2/5
# HumanEval/10
Implement a file **`solution.py`** that completes the function below. Keep the given name and signature; your file must define it at module level.
```python
def is_palindrome(string: str) -> bool:
""" Test if given string is a palindrome """
return string == string[::-1]
def make_palindrome(string: str) -> str:
""" Find the shortest palindrome that begins with a supplied string.
Algorithm idea is simple:
- Find the longest postfix of supplied string that is a palindrome.
- Append to the end of the string reverse of a string prefix that comes before the palindromic suffix.
>>> make_palindrome('')
''
>>> make_palindrome('cat')
'catac'
>>> make_palindrome('cata')
'catac'
"""
```
<!-- imported from OpenAI HumanEval (HumanEval/10) -->
tests/test_he_010.py
# Auto-generated from OpenAI HumanEval HumanEval/10. Do not edit by hand.
from solution import * # noqa: F401,F403 (prompt helpers may be referenced by tests)
from solution import make_palindrome as candidate
METADATA = {
'author': 'jt',
'dataset': 'test'
}
def check(candidate):
assert candidate('') == ''
assert candidate('x') == 'x'
assert candidate('xyz') == 'xyzyx'
assert candidate('xyx') == 'xyx'
assert candidate('jerry') == 'jerryrrej'
def test_he_010():
check(candidate)
System prompt
You are an expert programmer. Solve the task exactly as specified. Output your solution as fenced code blocks using the required file name(s) and the exact function/type signatures requested. Prefer correctness; do not include prose outside code unless asked.
Proposed solution
```python
def is_palindrome(string: str) -> bool:
""" Test if given string is a palindrome """
return string == string[::-1]
def make_palindrome(string: str) -> str:
""" Find the shortest palindrome that begins with a supplied string.
Algorithm idea is simple:
- Find the longest postfix of supplied string that is a palindrome.
- Append to the end of the string reverse of a string prefix that comes before the palindromic suffix.
>>> make_palindrome('')
''
>>> make_palindrome('cat')
'catac'
>>> make_palindrome('cata')
'catac'
"""
if not string:
return string
# Find the longest suffix that is a palindrome
for i in range(len(string)):
suffix = string[i:]
if is_palindrome(suffix):
# The prefix to add is the reverse of the part before the suffix
prefix_to_add = string[:i][::-1]
return string + prefix_to_add
# Fallback (should not be reached for non-empty strings due to single char palindrome)
return string
```Test output (stdout)
. [100%] 1 passed in 0.01s