upper and lower triangle matrix

// Java program to print Lower  
// triangular and Upper triangular 
// matrix of an array 
class GFG 
{ 
    // method to form lower  
    // triangular matrix 
    static void lower(int matrix[][],  
                      int row, int col) 
    { 
        int i, j; 
        for (i = 0; i < row; i++) 
        { 
            for (j = 0; j < col; j++) 
            { 
                if (i < j) 
                { 
                    System.out.print("0" + " "); 
                } 
                else
                System.out.print(matrix[i][j] + " "); 
            } 
            System.out.println(); 
        } 
    } 
      
    // Method to form upper 
    // triangular matrix 
    static void upper(int matrix[][],  
                      int row, int col) 
    { 
        int i, j; 
        for (i = 0; i < row; i++) 
        { 
            for (j = 0; j < col; j++) 
            { 
                if (i > j) 
                { 
                    System.out.print("0" + " "); 
                } 
                else
                System.out.print(matrix[i][j] + " "); 
            } 
            System.out.println(); 
        } 
    } 
       
    // Driver Code 
    public static void main(String args[]) 
    { 
        int matrix[][] = {{1, 2, 3},  
                          {4, 5, 6},  
                          {7, 8, 9}}; 
        int row = 3, col = 3; 
          
        System.out.println("Lower triangular matrix: "); 
        lower(matrix, row, col); 
          
        System.out.println("Upper triangular matrix: "); 
        upper(matrix, row, col); 
    } 
}