Python While Loops
January 17th 2020 449

Control Statements
Loops
In general, statements are executed sequentially − The first statement in a function is executed first, followed by the second, and so on. There may be a situation when you need to execute a block of code several number of times. A loop statement allows us to execute a statement or group of statements multiple times.
Python programming language provides the following types of loops to handle looping requirements.
while loop
for loop
nested loops
Loop Control Statements
The Loop control statements change the execution from its normal sequence. When the execution leaves a scope, all automatic objects that were created in that scope are destroyed.
Python supports the following control statements.
break
: Terminates the loop statement and transfers execution to the statement immediately following the loop.continue
: Causes the loop to skip the remainder of its body and immediately retest its condition prior to reiterating.pass
: Used when a statement is required syntactically but you do not want any command or code to execute.
iterable
It is a sequence of values like string
, list
, tuple
, dictionary
, range()
Syntax:
for item in iterable:
# do something on item
Syntax:
while expression:
# iterates till the condition is true
The while Loop
Repeats a statement or group of statements while a given condition is TRUE. It tests the condition before executing the loop body.
Syntax:
while expression:
# iterates till the condition is true
Example:
The break Statement
With the break statement we can stop the loop even if the while condition is true:
Example:
The continue Statement
With the continue statement we can stop the current iteration, and continue with the next: