Search a string in Matrix Using Split function in Java

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Given a string str and a matrix mat[][] of lowercase English alphabets, the task is to find whether the string str appears in the matrix (either row-wise or column-wise).

Examples:

Input: str = "GFG"
            mat[][] = {{'G', 'E', 'E', 'K', 'S'}, 
                             {'F', 'O', 'R', 'A', 'N'}, 
                             {'G', 'E', 'E', 'K', 'S'}}
Output: Yes
GFG is present in the first column.

Input: str = "SSS"
            mat[][] = {{'G', 'E', 'E', 'K', 'S'}, 
                              {'F', 'O', 'R', 'A', 'N'}, 
                              {'G', 'E', 'E', 'K', 'S'}}
Output: No

Approach:

If the search string is present in any row of the matrix the following results will be produced by the split function:

If the string occupies the whole row then the split function will return an array of length zero.

If the string is present in between characters then the array length will be greater than one.

If the array length is one then three possible cases can be there-

The string occurs in first half.

The string occurs in second half.

The string is not present in that row.

To search the string column wise transpose the matrix and repeat step one.

Print Yes if the string is found else print No.

Below is the implementation of the above approach:

Java

// Java program to search a string in 
// the matrix using split function 
import java.util.*; 
public class GFG { 
  
    // Function to check the occurrence of string in the matrix 
    public static int check(String[] matrix, String string) 
    { 
        // Looping the contents in the matrix 
        for (String input : matrix) { 
  
            // using split operator 
            String[] value = input.split(string); 
  
            if (value.length >= 2 || value.length == 0) { 
                return 1; 
            } 
            else if (value.length == 1
                    && input.length() != value[0].length()) { 
                return 1; 
            } 
        } 
        return 0; 
    } 
  
    // Function to transpose the given matrix 
    public static String[] vertical(String[] matrix) 
    { 
        String[] vertical_value = new String[(matrix[0].length())]; 
        for (int i = 0; i < matrix[0].length(); i++) { 
            String temp = ""; 
            for (int j = 0; j < matrix.length; j++) 
                temp += matrix[j].charAt(i); 
            vertical_value[i] = temp; 
        } 
  
        // returning the transposed matrix 
        return vertical_value; 
    } 
  
    // Driver code 
    public static void main(String[] args) 
    { 
  
        // Input matrix of characters 
        String[] matrix = { "GEEKS", "FORAN", "GEEKS" }; 
  
        // element to be searched 
        String search = "GFG"; 
  
        // Transpose of the matrix 
        String[] verticalMatrix = vertical(matrix); 
  
        // Searching process 
        int horizontal_search = check(matrix, search); 
        int vertical_search = check(verticalMatrix, search); 
  
        // If found 
        if (horizontal_search == 1 || vertical_search == 1) 
            System.out.println("Yes"); 
        else
            System.out.println("No"); 
    } 
} 

Output

Yes

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