# A jupyter notebook is composed by one or more cells.
# There are two main cells: Code and Markdown.
# A code cell is used to write and execute your codes.
# A markdown cell is used to write text descriptions, notes, formulas or include graphics and images.
# On a markdown cell, you can format your content by using Markdown, HTML, or LaTeX codes.
# During our tutorial, you are expected to write only python codes.
# Interested readers may also use markdown cells, but it is not necesary to complete our tutorial. 

#
# We explain basic usage of cells in Jupyter notebooks here
#

# This is the first cell in this notebook.
# You can write Python code here, 
# and then EXECUTE/RUN it by
# 1) pressing CTRL+ENTER or SHIFT+ENTER
# 2) clicking "Run" on the menu


# here are few lines of python code

print("hello world")
str="*"
for i in range(10):
    print(str)
    str+="*"

# after executing this cell, the outcomes will immedeately appear after this cell
#     you can change the range above and re-run this cell

# This is the second cell in this notebook. 
#
# By using menu item "Insert", you can add a new cell before or after the active cell.
#     When a cell is selected, you may delete it by using menu item "Edit".
#
# As you may notice, there are other editing options under "Edit",
#     for example, copy/cut-paste cells and split-merge cells.
#

%%writefile first.py 

print("hello world")

str="*"
for i in range(5):
    print(str)
    str+="*"  

%run first.py


# %load first.py

print("hello world")

str="*"
for i in range(5):
    print(str)
    str+="*"  


