_1062.java

packagecom.fishercoder.solutions.secondthousand;

importjava.util.HashSet;
importjava.util.Set;

publicclass_1062 {
publicstaticclassSolution1 {
/*
 * My completely original solution, although kind of brute-force, on 1/20/2022.
 * Two pointer technique:
 * j starts from the right, i starts from the left,
 * as soon as we are able to find a repeated substring, we return.
 */
publicintlongestRepeatingSubstring(Strings) {
Set<String> seen = newHashSet<>();
for (intj = s.length() - 1; j > 0; j--) {
for (inti = 0; i + j <= s.length(); i++) {
if (!seen.add(s.substring(i, i + j))) {
returnj;
 }
 }
seen.clear();
 }
return0;
 }
 }
}