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PYTHON—CONDITIONALS

                                          AND LOOPS




                  There are situations in life when we need to decide based on a situation. For example, if it
                  rains, I will stay at home or else I shall visit the market. Similar situations arise in programming
                  as well, where we need to make some decisions and based on these decisions, execute a
                  set of commands. We need to determine which action is to be taken and which statement
                  is to be executed, if the outcome is true or false. In this chapter, we will learn about decision
                  making statements of Python.


                  DECISION MAKING STATEMENTS
                  Decision making in Python is done by called conditional statements which decide the flow
                  of program execution. The following conditional statements are available in Python:

                      if statement
                      if...else statement
                      Nested if statement
                      if…elif…else ladder

                  The if Statement
                  The  if  statement  is  the  simplest  conditional  statement.          Test Expression    False
                  Here, a statement or a collection of statements within the

                  if block is executed only if a certain condition or expression                  True
                  evaluates to True. If the condition evaluates to False, then
                  the control of execution is passed to the next statement after            Body of if
                  the if block. The syntax of the if statement is given below:

                  Syntax:
                                                                                          Statement just
                  if (Test Expression):                                                      below if
                      Indented statement block

                  # if block ends here

                   Program 1: To find the sum of first 5 natural numbers.


















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