import random


class Matrix:
    def __init__(self, rows, cols):
        self.rows = rows
        self.cols = cols
        self.data = []
        
        for i in range(0, rows):
            self.data.append([0 for _ in range(0, cols)])

    @staticmethod
    def from_list(lst):
        m = Matrix(len(lst), 1)
        m.map(lambda x, i, j: lst[i])
        return m

    @staticmethod
    def product(a, b):
        """Matrix product"""
        if a.cols != b.rows:
            return None

        result = Matrix(a.rows, b.cols)
        result.map(lambda x, i, j: sum([a.data[i][k] * b.data[k][j] for k in range(0, a.cols)]))

        return result

    @staticmethod
    def transpose(m):
        """Transpose a matrix"""
        result = Matrix(m.cols, m.rows)
        result.map(lambda x, i, j: m.data[j][i])
        return result

    @staticmethod
    def subtract(a, b):
        result = Matrix(a.rows, a.cols)
        result.map(lambda x, i, j: a.data[i][j] - b.data[i][j])
        return result

    @staticmethod
    def clone(m):
        result = Matrix(m.rows, m.cols)
        result.map(lambda x, i, j: m.data[i][j])
        return result

    def map(self, fun):
        """Execute a function on every element of the list, use the return value as the new value of the element"""
        for i in range(0, self.rows):
            for j in range(0, self.cols):
                self.data[i][j] = fun(self.data[i][j], i, j)

    def randomize(self):
        """Fill the matrix with random integers"""
        self.map(lambda x, i, j: random.randint(-1, 1))

    def multiply(self, n):
        """Hadamard or scalar product"""
        if type(n) is Matrix:
            self.map(lambda x, i, j: x * n.data[i][j])
        else:
            self.map(lambda x, i, j: x * n)

    def add(self, n):
        """Entrywise or scalar addition"""
        if type(n) is Matrix:
            self.map(lambda x, i, j: x + n.data[i][j])
        else:
            self.map(lambda x, i, j: x + n)

    def print(self):
        """Pretty print the matrix"""
        for row in self.data:
            for elem in row:
                print(elem, end='\t')
            print()

    def to_list(self):
        """Returns the internal matrix as a list"""
        lst = []
        self.map(lambda x, i, j: lst.append(x))
        return lst