using System; 

public class GFG { 

    static void printDiagonalSums(int [,]mat, 

                                        int n) 

    { 

        int principal = 0, secondary = 0; 

        for (int i = 0; i < n; i++) { 

            for (int j = 0; j < n; j++) { 

                // Condition for principal 

                // diagonal 

                if (i == j) 

                    principal += mat[i,j]; 

                // Condition for secondary 

                // diagonal 

                if ((i + j) == (n - 1)) 

                    secondary += mat[i,j]; 

            } 

        } 

        Console.WriteLine("Principal Diagonal:"

                                  + principal); 

        Console.WriteLine("Secondary Diagonal:"

                                  + secondary); 

    } 

    // Driver code 

    static public void Main () 

    { 

        int [,]a = { { 1, 2, 3, 4 }, 

                     { 5, 6, 7, 8 },  

                     { 1, 2, 3, 4 }, 

                     { 5, 6, 7, 8 } }; 

        printDiagonalSums(a, 4); 

    } 

}