// matrix_sum_debug.c 
//
// Written by YOUR-NAME (YOUR-ZID)
// on TODAYS-DATE 
//
// Prints the sum of all elements in the matrix and the
// sum of elements along the top-left to bottom-right diagonal. 

#include <stdio.h>

#define SIZE 5

// Function Prototypes
int full_sum(int matrix[SIZE][SIZE]);

int main(void) {
    int matrix[SIZE][SIZE] = {
        { 1, 2, 3, 4, 5 },  
        { 8, 3, 2, 77, 1 }, 
        { 0, 0, 0, 0, 0 }, 
        { 1, 2, 23, 4, 5 }, 
        { 1, 44, 3, 0, 1 },   
    };

    printf("Full sum: %d\n", full_sum(matrix));
    printf(
        "Sum of top-left to bottom-right diagonal: %d\n", 
        diagonal_sum(matrix)
    );
    return 0;
}

// Calculates the sum of all elements in a 2D matrix
int full_sum(int matrix[SIZE][SIZE]) {
    int sum;
    for (int i = 1; i < SIZE; i++) {
        for (int j = 1; j < SIZE; j++) {
            sum = sum + matrix[j][j];
        }
    }
    return sum;
}

// Calculates the sum of elements along the top-left to bottom-right diagonal
// in a 2D matrix
int diagonal_sum(int matrix[SIZE][SIZE]) {
    int sum = 0;
    for (int i = 0; i < SIZE; i++) {
        for (int j = 0; j < SIZE; j++) {
            if (i != j) {
                sum++;
            }
        }
    }
    return sum;
}