题解 | 计算矩阵的积

def matrixmul(a,b):
    a_col = len(a[0])
    a_row = len(a)
    b_col = len(b[0])
    b_row = len(b)
    if a_col != b_row:
        return -1
    else:
        mul_ans = []
        for i in range(a_row):
            a_vec = a[i]
            row_ans = []
            for k in range(b_col):
                ans = 0
                for j in range(len(a_vec)):
                    ans += a_vec[j] * b[j][k]
                row_ans.append(ans)
            mul_ans.append(row_ans)
        return mul_ans

# 主程序
if __name__ == "__main__":
    # 输入矩阵
    matrix_inputa = input()
    matrix_inputb = input()

    # 处理输入
    import ast
    matrixa = ast.literal_eval(matrix_inputa)
    matrixb = ast.literal_eval(matrix_inputb)

    # 调用函数计算逆矩阵
    output = matrixmul(matrixa,matrixb)
    
    # 输出结果
    print(output)