LeetCode-in-Java
3083. Existence of a Substring in a String and Its Reverse
Easy
Given a string s, find any substring of length 2 which is also present in the reverse of s.
Return true if such a substring exists, and false otherwise.
Example 1:
Input: s = “leetcode”
Output: true
Explanation: Substring "ee" is of length 2 which is also present in reverse(s) == "edocteel".
Example 2:
Input: s = “abcba”
Output: true
Explanation: All of the substrings of length 2 "ab", "bc", "cb", "ba" are also present in reverse(s) == "abcba".
Example 3:
Input: s = “abcd”
Output: false
Explanation: There is no substring of length 2 in s, which is also present in the reverse of s.
Constraints:
1 <= s.length <= 100sconsists only of lowercase English letters.
Solution
public class Solution {
public boolean isSubstringPresent(String s) {
if (s.length() == 1) {
return false;
}
StringBuilder revSb = new StringBuilder();
for (int i = s.length() - 1; i >= 0; i--) {
revSb.append(s.charAt(i));
}
String rev = revSb.toString();
for (int i = 0; i < s.length() - 1; i++) {
String sub = s.substring(i, i + 2);
if (rev.contains(sub)) {
return true;
}
}
return false;
}
}