
#define CATCH_CONFIG_MAIN
#include <catch2/catch.hpp>

int sumMainDiagonal(const int arr[][3], int size);

TEST_CASE("Sum of main diagonal for 3x3 matrix with consecutive numbers", "[sumMainDiagonal]") {
    int matrix[3][3] = {
        {1, 2, 3},
        {4, 5, 6},
        {7, 8, 9}
    };
    int result = sumMainDiagonal(matrix, 3);
    REQUIRE(result == 15); // 1 + 5 + 9 = 15
}

TEST_CASE("Sum of main diagonal for 3x3 matrix with zeros except diagonal", "[sumMainDiagonal]") {
    int matrix[3][3] = {
        {2, 0, 0},
        {0, 4, 0},
        {0, 0, 6}
    };
    int result = sumMainDiagonal(matrix, 3);
    REQUIRE(result == 12); // 2 + 4 + 6 = 12
}

TEST_CASE("Sum of main diagonal for 3x3 matrix with all elements 1", "[sumMainDiagonal]") {
    int matrix[3][3] = {
        {1, 1, 1},
        {1, 1, 1},
        {1, 1, 1}
    };
    int result = sumMainDiagonal(matrix, 3);
    REQUIRE(result == 3); // 1 + 1 + 1 = 3
}

TEST_CASE("Sum of main diagonal for 3x3 matrix with negative numbers", "[sumMainDiagonal]") {
    int matrix[3][3] = {
        {-1, 0, 0},
        {0, -2, 0},
        {0, 0, -3}
    };
    int result = sumMainDiagonal(matrix, 3);
    REQUIRE(result == -6); // -1 + -2 + -3 = -6
}

test.cpp

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Challenge: Sum of Main Diagonal

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