While loop

What is While loop in Python?
  • A While loop in Python is used to execute a set of statements/ iterate over a block of code repeatedly as long as the given condition is true.
  • While loop is preferred when we don't know the number of iterations.
Syntax:
                    while condition:
                            body statements
  • The body statement of the while loop is separated from the rest of the code using indentation [tab].

For loop

What is For loop in Python?
  • A for loop in python has the ability to iterate over items of any sequence (List, tuple, string) or any other iterable objects.
  • Iterating over a sequence is called traversal.
Syntax:
                    for var in sequence:
                            body statements
    
  • Here, var is a variable that is used to take the next values from the sequence on every iteration until the end of the sequence is reached.

If, If...else, If...elif...else, Nested If

What is selection statement in Python?
  • In some cases in programming, Our program has to decide whether the following block of codes needs to be executed or not, based on some conditions.
  • Such Decision making statements/selection statements decide the direction of flow of program execution.
  • Decision making statements/selection statements available in Python are
        • if (Simple If)
        • if-else
        • else-if ladder
        • Nested if
  • In python, body statements inside the selection statement are indicated by the indentation. The very first unindented line marks the end of the selection statements.

Dictionaries in Python

What is Dictionary in python?
  • Dictionary is an unordered collection of data in the form of key-value pair.
  • First element in the key-value pair is the key and the second element is the value.
  • Like list, dictionaries are mutable.
Creating a dictionary
  • Dictionaries are written inside curly brackets ({}) with comma-separated key-value pairs.

Tuples in Python

1) What is Tuple?
  • Just like List, Tuple is a collection of ordered element. But the difference between list and Tuple is, tuples are immutable i.e. the elements in the Tuple cannot be changed, once it is assigned.
  • Tuples also can store both homogeneous and heterogeneous elements.
2) Creating a Tuple
  • Tuples can be created by placing all the elements separated by commas inside parentheses().