Problem
Given a string s, return the longest palindromic substring in s.
Example 1:
Input: s = “babad” Output: “bab” Explanation: “aba” is also a valid answer.
Example 2:
Input: s = “cbbd” Output: “bb”
Constraints:
1 <= s.length <= 1000 s consist of only digits and English letters.
INPUT
{
"s": "abba"
}
EXPECTED
"abba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonhighnoon"
}
EXPECTED
"noon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xyzabcbaxyz"
}
EXPECTED
"abcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "racecarannakayak"
}
EXPECTED
"racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcab"
}
EXPECTED
"aba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdeedcbafedcbe"
}
EXPECTED
"abcdeedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "a1b2c3d4c3b2a"
}
EXPECTED
"a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abccccba"
}
EXPECTED
"abccccba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonnoonnoon"
}
EXPECTED
"noonnoonnoon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeeedddccbaa"
}
EXPECTED
"ddeeeedd"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz"
}
EXPECTED
"A"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "acbbac"
}
EXPECTED
"bb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "forgeeksskeegfor"
}
EXPECTED
"geeksskeeg"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonlevelnoon"
}
EXPECTED
"noonlevelnoon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abbaabba"
}
EXPECTED
"abbaabba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "rotor1234321rotor"
}
EXPECTED
"rotor1234321rotor"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaaaabaaa"
}
EXPECTED
"aaabaaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefghihgfedcba"
}
EXPECTED
"abcdefghihgfedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "civicdeifiedrotorlevel"
}
EXPECTED
"deified"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aquickbrownfoxjumpsoverthelazydog"
}
EXPECTED
"a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "zyxwvutsrqponmlkjihgfedcbaedcba"
}
EXPECTED
"z"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabcddeffedcba"
}
EXPECTED
"deffed"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "pppppppppppppppppppppppppppppppp"
}
EXPECTED
"pppppppppppppppppppppppppppppppp"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaabaaaa"
}
EXPECTED
"aaabaaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeeedddccbbaa"
}
EXPECTED
"ddeeeedd"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "a1b2c3d4e5f6g7h8i9j0j9i8h7g6f5e4d3c2b1a"
}
EXPECTED
"a1b2c3d4e5f6g7h8i9j0j9i8h7g6f5e4d3c2b1a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "mississippi"
}
EXPECTED
"ississi"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "zxcvbnmlkjhgfdsapoiuytrewqpoiuytrewqpoiuytrewqpoiuytrewq"
}
EXPECTED
"z"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "deifiedrotorlevel"
}
EXPECTED
"deified"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdedcba"
}
EXPECTED
"abcdedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaa"
}
EXPECTED
"aaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaaaa"
}
EXPECTED
"aaaaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "racecar"
}
EXPECTED
"racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "a"
}
EXPECTED
"a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefg"
}
EXPECTED
"a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeeffgg"
}
EXPECTED
"eee"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaaa"
}
EXPECTED
"aaaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdedcba12321"
}
EXPECTED
"abcdedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xxyyyxyxyxyxyxyxxyyxyxyxyxyxyx"
}
EXPECTED
"xyxyxyxyxyx"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "thisisanexamplewithlongestpalindromeonyxdxyxdx"
}
EXPECTED
"xdxyxdx"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": 12345678987654320
}
EXPECTED
12345678987654320
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xyzaaazyxzyzyxyz"
}
EXPECTED
"xyzaaazyx"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "12321abcdcba45654"
}
EXPECTED
"abcdcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "012210"
}
EXPECTED
"012210"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "tattarrattat"
}
EXPECTED
"tattarrattat"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbabbaa"
}
EXPECTED
"aabbabbaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcaba12321"
}
EXPECTED
12321
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcaba"
}
EXPECTED
"aba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xyxxyxyxyxyxyxyx"
}
EXPECTED
"xyxyxyxyxyxyx"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "1234321abcdefghgfedcba"
}
EXPECTED
"abcdefghgfedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abababababababababababababababababababababababababababababababab"
}
EXPECTED
"bababababababababababababababababababababababababababababababab"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcabaxxxabcdcba"
}
EXPECTED
"abcdcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "12321abccba45654"
}
EXPECTED
"abccba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "12321abcdedcbavcvcv"
}
EXPECTED
"abcdedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcbaekayakecivic"
}
EXPECTED
"ekayake"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonmoonnoon"
}
EXPECTED
"oonnoo"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcbaxxxxxabcdcba"
}
EXPECTED
"cbaxxxxxabc"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonhighnoonnoon"
}
EXPECTED
"noonnoon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "ac"
}
EXPECTED
"a"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonmidnightnoon"
}
EXPECTED
"noon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcba12321defedcba"
}
EXPECTED
"defed"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbabaaaabbaaabaaabbbbbaaaaaabbbaaaabbbbaaabbaabbbaaaabbbaaabbbbaaabbaabbaabbab"
}
EXPECTED
"bbaaabbbbaaabb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "ababababababababa"
}
EXPECTED
"ababababababababa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonnoonnoonnoonnoonnoon"
}
EXPECTED
"noonnoonnoonnoonnoonnoon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abccbaabacdfgdcaba"
}
EXPECTED
"abccba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "racecarxracecar"
}
EXPECTED
"racecarxracecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "madamracecarlevel"
}
EXPECTED
"racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "babcbabcbabcba"
}
EXPECTED
"abcbabcbabcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcabaabacdfgdcaba"
}
EXPECTED
"dcabaabacd"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "babad"
}
EXPECTED
"aba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "madamintanimadaminabba"
}
EXPECTED
"animadamina"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonracecarracecar"
}
EXPECTED
"racecarracecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "zzzzzzzzzzzz"
}
EXPECTED
"zzzzzzzzzzzz"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "racecar2racecar"
}
EXPECTED
"racecar2racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "zxyabcddcbaabczyx"
}
EXPECTED
"abcddcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "deeee"
}
EXPECTED
"eeee"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcabacdfgdcaba"
}
EXPECTED
"dcabacd"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": 1234543216789876
}
EXPECTED
123454321
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcbaaabcba"
}
EXPECTED
"abcbaaabcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdedcbaefghihgfexyzzyx"
}
EXPECTED
"efghihgfe"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noon"
}
EXPECTED
"noon"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefgfebac"
}
EXPECTED
"efgfe"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "levelhannahlevel"
}
EXPECTED
"levelhannahlevel"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xxyyzzzyyxx"
}
EXPECTED
"xxyyzzzyyxx"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcddcbaabcddcbaxyzzyx"
}
EXPECTED
"abcddcbaabcddcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "racecar12321racecar"
}
EXPECTED
"racecar12321racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdeffedcba"
}
EXPECTED
"abcdeffedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "civicracecar"
}
EXPECTED
"racecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "levelmadammadam"
}
EXPECTED
"madammadam"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "zxyaxzyaz"
}
EXPECTED
"z"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefedcba"
}
EXPECTED
"abcdefedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "cbbd"
}
EXPECTED
"bb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": 12321321321321320
}
EXPECTED
12321
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xyzzyxcbaapqrqpabczyzyx"
}
EXPECTED
"apqrqpa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcaba123321"
}
EXPECTED
123321
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abacdfgdcabaxxxxxabcdcba"
}
EXPECTED
"baxxxxxab"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabcdcbadefedcbaa"
}
EXPECTED
"abcdcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefghijiklmnopqrstuvwxyzzyxwvutsrqponmlkjihgfedcba"
}
EXPECTED
"klmnopqrstuvwxyzzyxwvutsrqponmlk"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "bananaananab"
}
EXPECTED
"bananaananab"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeedcba"
}
EXPECTED
"deed"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "noonhighnoonnoonhighnoon"
}
EXPECTED
"hnoonnoonh"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "babaddabba"
}
EXPECTED
"baddab"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcba"
}
EXPECTED
"abcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abababababababababababababababababababababababababababababababbababa"
}
EXPECTED
"babababababababababababababababababababababababababababababab"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdeedcba1234321xyzzyx"
}
EXPECTED
"abcdeedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabb"
}
EXPECTED
"bb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "mamamamamamamamama"
}
EXPECTED
"amamamamamamamama"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdefgfedcba"
}
EXPECTED
"abcdefgfedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcbabcba"
}
EXPECTED
"abcbabcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "xyzzzzyxabcdefedcba"
}
EXPECTED
"abcdefedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "banana"
}
EXPECTED
"anana"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcbcbcbcbcbcbcbcbcbcbcbcb"
}
EXPECTED
"bcbcbcbcbcbcbcbcbcbcbcbcb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "anana"
}
EXPECTED
"anana"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "bcbabcbabcba"
}
EXPECTED
"bcbabcbabcb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeeeddccbbbaa"
}
EXPECTED
"bbccddeeeeddccbb"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "12321abcdedcba45654"
}
EXPECTED
"abcdedcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeffgg"
}
EXPECTED
"gg"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "levelracecardeifiedracecar"
}
EXPECTED
"racecardeifiedracecar"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aaaaabbbbbaaaa"
}
EXPECTED
"aaaabbbbbaaaa"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abccba"
}
EXPECTED
"abccba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdcba12321xyzzyx"
}
EXPECTED
"abcdcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "12321abcba21321"
}
EXPECTED
"abcba"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "aabbccddeeffgghhiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz"
}
EXPECTED
"zz"
OUTPUT
STDOUT
STDERR
INPUT
{
"s": "abcdcbaxxxabcdcbaabcdcbaxxxabcdcba"
}
EXPECTED
"abcdcbaxxxabcdcbaabcdcbaxxxabcdcba"
OUTPUT
STDOUT
STDERR