LeetCode 0459. Repeated Substring Pattern Solution in Java, C++, Python & More | Explanation + Code

Description

Given a string s, check if it can be constructed by taking a substring of it and appending multiple copies of the substring together.

 

Example 1:

Input: s = "abab"
Output: true
Explanation: It is the substring "ab" twice.

Example 2:

Input: s = "aba"
Output: false

Example 3:

Input: s = "abcabcabcabc"
Output: true
Explanation: It is the substring "abc" four times or the substring "abcabc" twice.

 

Constraints:

• 1 <= s.length <= 104
• s consists of lowercase English letters.

Solutions

Solution 1

PythonJavaC++GoTypeScriptRust

class Solution: def repeatedSubstringPattern(self, s: str) -> bool: return (s + s).index(s, 1) < len(s)(code-box)

class Solution { public boolean repeatedSubstringPattern(String s) { String str = s + s; return str.substring(1, str.length() - 1).contains(s); } }(code-box)

class Solution { public: bool repeatedSubstringPattern(string s) { return (s + s).find(s, 1) < s.size(); } };(code-box)

func repeatedSubstringPattern(s string) bool { return strings.Index(s[1:]+s, s) < len(s)-1 }(code-box)

function repeatedSubstringPattern(s: string): boolean { return (s + s).slice(1, (s.length << 1) - 1).includes(s); }(code-box)

impl Solution { pub fn repeated_substring_pattern(s: String) -> bool { (s.clone() + &s)[1..s.len() * 2 - 1].contains(&s) } }(code-box)