Naive_String_Matching.java

import java.util.Scanner;

class Naive_String_Matching
{
    public static void search(String text, String pattern)
    {
        int lengthText = text.length();
        int lengthPattern = pattern.length();

        for(int i = 0; i <= lengthText - lengthPattern; i++)
        {
            int j;

            for(j = 0; j < lengthPattern; j++)
                if(text.charAt(i + j) != pattern.charAt(j))
                    break;

            if(j == lengthPattern)
               System.out.println("Pattern found at " + (i + 1));
        }
    }

    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter text");
        String text = sc.nextLine();
        System.out.println("Enter pattern");
        String pattern = sc.nextLine();
        Naive_String_Matching obj = new Naive_String_Matching();
        obj.search(text, pattern);
    }
}

/* 
Input:
text = "namanchamanbomanamansanam"
pattern = "aman"

Output:
Pattern found at 2
Pattern found at 8
Pattern found at 17
*/