Java Program to find the longest repeating sequence in a string

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public class LongestRepeatingSequence {  
    //Checks for the largest common prefix  
    public static String lcp(String s, String t){  
        int n = Math.min(s.length(),t.length());  
        for(int i = 0; i < n; i++){  
            if(s.charAt(i) != t.charAt(i)){  
                return s.substring(0,i);  
            }  
        }  
        return s.substring(0,n);  
    }  
  
    public static void main(String[] args) {  
        String str = "acbdfghybdf";  
        String lrs="";  
        int n = str.length();  
        for(int i = 0; i < n; i++){  
            for(int j = i+1; j < n; j++){  
                //Checks for the largest common factors in every substring  
                String x = lcp(str.substring(i,n),str.substring(j,n));  
                //If the current prefix is greater than previous one  
                //then it takes the current one as longest repeating sequence  
                if(x.length() > lrs.length()) lrs=x;  
            }  
        }  
        System.out.println("Longest repeating sequence: "+lrs);  
    }  
}  

 


Output:

Longest repeating sequence: bdf