Recursion + two pointers

Recursion subproblem; ஒவ்வொரு level-லும் slice-இல் two pointers.

Try this in Python

def is_palindrome_range(s: str, lo: int, hi: int) -> bool:
    while lo < hi:
        if s[lo] != s[hi]:
            return False
        lo += 1
        hi -= 1
    return True


print(is_palindrome_range("racecar", 0, 6))

Key takeaways

• Palindrome — recursive base.
• Advanced string DP.
• Base case length 0/1.