# Learning Python- Basic course: Day 2, Statements, Comments and Indentation


Originally published on the dev.to platform here

# ✌️Hi all! Welcome to the second day of the course! Today let us learn about some Python syntax.


Statements in Python Statements in Python are of three types

  1. Expressions- Statements which perform actions like addition, division, or any other such operations. Here are a few sample commands.

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  1. Assignments- The statements giving values to variables are called assignments.

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  1. Declarations - Functions, classes in python are declared by using the keyword "def". The function declaration must end with semicolon ":"

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Indentation in Python- We need to leave spaces after every loops and function declarations. Brackets in Java are replaced by indentation in Python. If Indentation is not respected, this error is generated.

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Moreover, every loop must end by a semicolon ':'

Comments in Python - Comments in Python begin with a '#' These commands are ignored by the interpreter and used to make the program clearer for the developers.

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Comments are an essential part of documentation. Proper documentation is a good programming habit. More about it [here] (https://dev.to/aatmaj/document-today-or-repent-tommorrow-1mg8).


Now, let us see a sample Python program-

print("Program to accept student details.")
#here, print() takes one string argument.

#input()  takes one string argument which it prints out.
#input()  returns one string argument
Rollno=int(input("Enter Roll Number "))
#int() converts the string into an integer type

name=input("Please enter a name ")

avg=float(input("enter percentage scored "))
#float() converts the string into an float type

print("Rollno of the student ",Rollno)
print("Name of the student ",name)
print("Percentage scored",avg,"%")
#here print() takes multiple arguments which it prints in the sequential order

Output-

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Note, that as we need to operate upon the numbers inputted, we have used the int() method. But if we input a character or string in place of the int, we will get the following error.

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In order to prevent such errors, error handling must be dont, which will be covered in this course...

Here is another program which gives the value of net resistance in parallel

a=int(input("Please enter first resistance "))
b=int(input("Please enter second resistance "))
c=(a*b)/(a+b)
#write the brackets carefully
print("answer is",c)

output-

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More about operators in Python will be in the next blog...

Exercise----

  1. Write a code in Python to find average of four numbers in one line, without declaring any variables.
  2. Write a code to reverse a three digit number in Python. (Answers can be found here)

To be continued....😏


So friends that's all for this part. 😊 Hope you all are enjoying.😎 Please let me know in the comment section if you liked it or not. 🧐 And don't forget to like the post if you did. 😍 I am open to any suggestions or doubts. 🤠 Just post in the comments here or gmail me. 😉 Thank you for being so patient.👍

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