Example: Calculate Matrix Trace in C++

// Calculate Matrix Trace
#include <iostream>
#include <vector>

// Function to calculate the trace of a square matrix
int calculateTrace(const std::vector<std::vector<int>>& matrix, int rows, int cols) {
    // Check if the matrix is square
    if (rows != cols) {
        std::cout << "Error: Trace is defined only for square matrices." << std::endl;
        return -1; // Indicate an error
    }

    int trace = 0;
    // Iterate through the main diagonal
    for (int i = 0; i < rows; ++i) {
        trace += matrix[i][i];
    }
    return trace;
}

int main() {
    // Example matrix (3x3)
    std::vector<std::vector<int>> myMatrix = {
        {1, 2, 3},
        {4, 5, 6},
        {7, 8, 9}
    };

    int numRows = myMatrix.size();
    int numCols = myMatrix[0].size(); // Assumes non-empty rows

    // Calculate and print the trace
    int traceValue = calculateTrace(myMatrix, numRows, numCols);
    if (traceValue != -1) {
        std::cout << "Trace of the matrix: " << traceValue << std::endl;
    }

    return 0;
}