// Program to find sum of right diagonal or left diagnol elements of a matrix
import java.util.*;

public class diagonalsum {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int[][] a = new int[3][3];
        int sum = 0;  // Fixed: Declared sum variable
        
        // Input 4x4 matrix
        System.out.println("Enter elements of 3x3 matrix:");
        for(int i = 0; i < 3; i++) {
            for(int j = 0; j < 3; j++) {
                a[i][j] = sc.nextInt();
            }
        }
        
        // Calculate sum of left or right diagonal elements
        for(int i = 0; i < 3; i++) {
            for(int j = 0; j < 3; j++) {
                if(i==j ) { // use (i==j) for left diagonal and (i+j==n-1) for right diagonal
                    sum += a[i][j];
                }
            }
        }
        
        System.out.println("Sum of right diagonal elements: " + sum);
        sc.close();  // Close scanner
    }
}
//By 4x4 matrix it should be 3x3 matrix as the array is defined as 3x3