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#include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef long long ll;
typedef vector<vector<int>> matrix;
const int maxn = 1e5 + 10;
const int INF = 2e9;

matrix multiply_by_k(matrix A, int k) {
    matrix res = A;
    int n = (int) A.size(), m = (int) A[0].size();
    
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            res[i][j] *= k;
        }
    }
    return res;
}
matrix add_two_matrices(matrix A, matrix B) {
    int n_a = (int) A.size(), m_a = (int) A[0].size();
    int n_b = (int) B.size(), m_b = (int) B[0].size();
    
    if(n_a == n_b and m_a == m_b) {
        matrix res = A;
        for(int i = 0; i < n_a; i++) {
            for(int j = 0; j < m_a; j++) {
                res[i][j] = A[i][j] + B[i][j];
            }
        }
        return res;
    }
    cout << "Dimenziite na matricite treba da se isti za da mozhe da gi sobereme istite" << endl;
    return {{0}};
}
matrix subtract_two_matrices(matrix A, matrix B) {
    int n_a = (int) A.size(), m_a = (int) A[0].size();
    int n_b = (int) B.size(), m_b = (int) B[0].size();
    
    if(n_a != n_b or m_a != m_b) {
        cout << "Dimenziite na matricite treba da se isti za da mozhe da gi sobereme istite" << endl;
        return {{0}};
    }
    matrix res = A;
    for(int i = 0; i < n_a; i++) {
        for(int j = 0; j < m_a; j++) {
            res[i][j] = A[i][j] - B[i][j];
        }
    }
    return res;
}
matrix multiply_two_matrices(matrix A, matrix B) {
    int n_a = (int) A.size(), m_a = (int) A[0].size();
    int n_b = (int) B.size(), m_b = (int) B[0].size();
    
    if(m_a != n_b) {
        cout << "Matricite ne mozhat da se mnozhat" << endl;
        return {{0}};
    }
    matrix res(n_a, vector<int>(m_b, 0));
    for(int i = 0; i < n_a; i++) {
        for(int j = 0; j < m_b; j++) {
            int c = 0;
            for(int k = 0; k < n_a; k++) {
                c += A[i][k] * B[k][j];
            }
            res[i][j] = c;
        }
    }
    
    return res;
}
void print(matrix A) {
    int n = (int) A.size(), m = (int) A[0].size();
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            cout << A[i][j] << " ";
        }
        cout << endl;
    }
    cout << endl;
}
int main() {
    matrix A = {
        {1, 2},
        {3, 4}
        
    };
    matrix B = {
        {1, 2, 3},
        {4, 5, 6},
        
    };
    
    matrix multiplied_by_k = multiply_by_k(A, 2);
    print(multiplied_by_k);
    
    matrix add_two_matrix = add_two_matrices(A, B);
    print(add_two_matrix);
    
    
    matrix subtrac_two_matrix = subtract_two_matrices(A, B);
    print(subtrac_two_matrix);
    
    matrix multiplication_two_matrices = multiply_two_matrices(A, B);
    print(multiplication_two_matrices);
    return 0;
}